Characterization of electric properties of nanomaterials usually involves fabricating field effect transistors （FET） and deriving materials properties from device performances. However, the quality of electrode cont...Characterization of electric properties of nanomaterials usually involves fabricating field effect transistors （FET） and deriving materials properties from device performances. However, the quality of electrode contacts in FET devices heavily influences the device performance, which makes it difficult to obtain the intrinsic electric properties of nanomaterials. Dielectric force microscopy （DFM）, a contactless method developed recently, can detect the low-frequency dielectric responses of nanomaterials without electric contact, which avoids the influence of electric contact and can be used to study the intrinsic conductivity of nanomaterials. Here we study the influences of surface adsorbates on the conductivity of ZnO nanowires （NWs） by using FET and DFM methods. The conductivity of ZnO NW is much larger in N2 atmosphere than that in ambient environment as measured by FET device, which is further proven by DFM measurement that the ZnO NW exhibits larger dielectric response in N2 environment, and the influence of electrode contacts on measurement can be ruled out. Based on these results, it can be concluded that the adsorbates on ZnO NW surface highly influence the conductivity of ZnO NW rather than the electrode contact. This work also verifies the capability of DFM in measuring electric properties of nanomaterials.展开更多
The mass spectrometry of gold clusters stabilized by poly（N‐vinyl‐2‐pyrrolidone） （Au：PVP） re‐vealed the presence of Cl adsorbates derived from synthetic precursors, mainly on the Au34 and Au43 clusters. Chang...The mass spectrometry of gold clusters stabilized by poly（N‐vinyl‐2‐pyrrolidone） （Au：PVP） re‐vealed the presence of Cl adsorbates derived from synthetic precursors, mainly on the Au34 and Au43 clusters. Changes in the amount of Cl adsorbates on the Au clusters did not affect the catalytic prop‐erties for the aerobic oxidation of benzyl alcohol, suggesting that the Cl atoms were only weakly bound to the Au clusters. In contrast, the replacement of Cl with Br on the Au34 and Au43 clusters significantly suppressed activity, without any influence on the electronic structure. This result indi‐cated that the Br atoms were strongly bound to the Au clusters and sterically blocked their active sites. The substantial reduction of the catalytic activity by the Br adsorbates suggested that the Au34 and Au43 clusters made a major contribution to the catalytic activity of the Au：PVP.展开更多
Despite substantial efforts in developing high-performance catalysts for the oxygen reduction reaction(ORR),the persistent challenge lies in the high onset overpotential of the ORR,and the effect of the elec-trolyte s...Despite substantial efforts in developing high-performance catalysts for the oxygen reduction reaction(ORR),the persistent challenge lies in the high onset overpotential of the ORR,and the effect of the elec-trolyte solution cannot be ignored.Consequently,we have systematically investigated the impact of adsorbate species and concentration,as well as solution pH,on the ORR activity on Pt(111)and Pt(poly)electrodes.The results all tend to establish a linear quantitative relationship between the onset potential for ORR and the adsorption equilibrium potential of the adsorbate.This finding indicates the decisive role of adsorbates in the onset potential for ORR,suggesting that the adsorption potential of adsorbates can serve as an intuitive criterion for ORR activity.Additional support for this conclusion is derived from experimental results obtained from the oxygen evolution reaction on Pt(poly)with different adsorbate species and from the hydrogen evolution reaction on Pt(111)with iodine adsorption.We further propose both an empirical equation for the onset potential for ORR and the concept of a potential-regulated adsor-bate shielding effect to elucidate the influence of adsorbates on ORR activity.This study provides new insights into the high onset overpotential of the ORR and offers potential strategies for predicting and enhancingORRactivity inthefuture.展开更多
Developing efficient electrocatalysts for the oxygen evolution reaction(OER)under neutral conditions is important for microbial electrolysis cells(MECs).However,the OER kinetics in neutral electrolytes at present are ...Developing efficient electrocatalysts for the oxygen evolution reaction(OER)under neutral conditions is important for microbial electrolysis cells(MECs).However,the OER kinetics in neutral electrolytes at present are extremely sluggish,resulting in high overpotentials that greatly limit the energy conversion efficiencies of MECs.Previous studies failed to probe the adsorbates on surface metal sites of catalysts at the atomic scale and elucidate their influence on the catalytic activities,which has impeded the rational design of efficient neutral OER catalysts with optimal surface structures.Here,using in situ transmission electron microscopy(TEM),in situ X-ray photoelectron spectroscopy(XPS)and in situ low-energy ion scattering studies,we have identified,for the first time,that the electrochemically activated adsorbates on surface metal sites play a critical role in boosting the neutral OER activities of Ru-Ir binary oxide(RuxIryO2)catalysts.The adsorbate-activated RuxIryO2on a glassy carbon electrode achieved a low overpotential of 324 m V at10 m A cm-2in neutral electrolyte,with a 36-fold improvement in turnover frequency compared with that of Ir O2benchmark.Upon application in an MEC system,the resulting full cell showed a decreased voltage of 1.8 V,200 m V lower than the best value reported to date,facilitating efficient synthesis of poly(3-hydroxybutyrate)from bioelectrochemical CO_(2)reduction.Density functional theory(DFT)studies revealed that the enhanced OER activity of RuxIryO2catalyst arose from local structural distortion of adjacent adsorbate-covered Ru octahedra at the catalyst surface and the consequently decreased adsorption energies of OER intermediates on Ir active center.展开更多
Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent resea...Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent research has significantly improved the performance of lignin-based hydrogels,suggesting their substantial potential in fields such as biomedicine,environmental science,and agriculture.This paper reviews the process of lignin extraction,systematically introduces synthesis strategies for preparing lignin-based hydrogels,and discusses the current state of research on these hydrogels in biomedical and environmental protection fields.It concludes by identifying the existing challenges in lignin hydrogel research and envisioning future prospects and development trends.展开更多
Resourceful food waste treatment is essential for promoting the sustainable development of anaerobic digestion and realizing a circular economy.In this study,biogas residue(BR)was used as a feedstock to produce highva...Resourceful food waste treatment is essential for promoting the sustainable development of anaerobic digestion and realizing a circular economy.In this study,biogas residue(BR)was used as a feedstock to produce highvalue-added products(gas,tar,and char-derived high-performance adsorbents)using pyrolysis technology(at 400–800℃).CaCO_(3),the major component of ash,significantly improved the quality of the pyrolysis product by decomposing into CO_(2) and CaO.The gasification reaction of CO_(2) with coke generated substantial CO and facilitated the formation of a rich pore structure in the char.CaO improved tar quality by contributing to secondary cracking reactions and reducing water content.The composite material formed exhibited excellent performance in wastewater treatment,with a maximum methylene blue adsorption capacity of 969.30 mg/g.The maximum adsorption of heavy metals Cu^(2+),Pb^(2+),and Cd^(2+)was 175.44,244.93,and 199.50 mg/g,respectively.The ash fraction on the ash-biochar composite material adsorbent surface enhanced pollutant removal by providing an alkaline adsorption environment and more oxygen-based n-π interaction sites.The economic analysis showed that the high value-added products obtained from the pyrolysis of BR make this process more productive than land use.展开更多
The increasing need for efficient,sustainable,and environmentally friendly adsorbent materials has driven interest in bio-based alternatives.Conventional silica-based adsorbents,while effective,are often brittle and e...The increasing need for efficient,sustainable,and environmentally friendly adsorbent materials has driven interest in bio-based alternatives.Conventional silica-based adsorbents,while effective,are often brittle and energy-intensive to produce.In contrast,wood offers a renewable and low-energy option with natural porosity suitable for adsorption.This study investigated the fabrication of wood sponge from tropical balsa(Ochroma bicolor)and pulai(Alstonia scholaris)wood through a dual-stage delignification process as a novel bio-based adsorbent.The process involved alkaline treatment using sodium sulfite(Na_(2)SO_(3))and sodium hydroxide(NaOH)at 100℃for 8,9,and 10 h,followed by bleaching process using hydrogen peroxide(H_(2)O_(2))at 100℃for 1,2,and 3 h.The treated samples were then rinsed to neutral pH,frozen at−20℃for 24 h,and freeze-dried at−50℃for 48 h.The results revealed a notable reduction in density and specific gravity,accompanied by increased weight loss and pore diameter size with prolonged delignification process.Optical changes showed increased translucency and layered structures,particularly in balsa wood.FTIR analysis confirmed a reduction in lignin and hemicellulose content,validating the chemical modification within the treated samples.The resulting wood sponges exhibited good porosity and adsorption capacity,ranging from 1.3 to 5.7 g/g.The optimal treatment—10 h of alkaline delignification followed by 3 h of H_(2)O_(2)bleaching—demonstrated the highest performance,highlighting the potential of tropical wood species as efficient,biodegradable,and eco-friendly adsorbent materials.展开更多
Selective extraction of precious metals from urban mines plays a crucial role in mitigating the risk of depletion of precious metal resources and reducing waste pollution.However,a major obstacle in precious metal ext...Selective extraction of precious metals from urban mines plays a crucial role in mitigating the risk of depletion of precious metal resources and reducing waste pollution.However,a major obstacle in precious metal extraction lies in the difficulty of distinguishing the subtle differences in the physicochemical characteristics between them,especially gold and palladium.Herein,a proton-driven separation system was presented for cascade recovery of gold and palladium from waste-printed circuit boards(W-PCBs)leachate using poly(amidoxime)(PAO)hydrogel.This exhibits an ultra-high capacity,extra-fast rate,and excellent selectivity for the extraction of Au(Ⅲ)and Pd(Ⅱ).Notably,the separation of Au(Ⅲ)and Pd(Ⅱ)can be achieved with high selectivity at pH=0,resulting in a remarkable separation factor of k_(Au(Ⅲ)/Pd(Ⅱ))=36.5.This was demonstrated to originate from the differential mechanism of PAO hydrogel for the capture of Au(Ⅲ)and Pd(Ⅱ)under proton-mediated conditions.Drawing inspiration from the mechanism,the proton-driven cascade recovery system demonstrates remarkable efficiency in sequentially recovering 99.92%of gold and 99.05%of palladium from W-PCBs acid leachate.This research opens up a strategy to precisely separate and recover precious metals from e-waste of urban mines.展开更多
Density functional theory(DFT)has helped propel the advance of electrocatalysis in the past two decades.In view of its massive use,it is worth asking how reliable DFT is for the prediction of adsorption energies,which...Density functional theory(DFT)has helped propel the advance of electrocatalysis in the past two decades.In view of its massive use,it is worth asking how reliable DFT is for the prediction of adsorption energies,which are paramount in computational electrocatalysis models.Here,we provide an experimental-computational approach to break down overall adsorption-energy errors into separate gas-phase and adsorbed-phase contributions.The method is evaluated using experimental data and various exchange-correlation functionals and materials for C-and O-containing species.Our main conclusion is that no functional is simultaneously accurate for adsorbates and molecules,as adsorbed-phase errors are visibly different from gas-phase errors.Importantly,total,gas-phase,and adsorbed-phase errors are correlated,revealing intrinsic DFT limitations and enabling the elaboration of swift correction routines.To illustrate the benefits of our approach,we deconvolute and correct all errors in CO_(2)electroreduction to CO and find an agreement with experiments close to chemical accuracy for numerous transition-metal electrodes and all scrutinized functionals.展开更多
Hospital wastewater contains complex pollutants,including residual organic dyes and antibiotic-resistant pathogens,posing severe risks to ecosystems and human health.Conventional adsorbents,constrained by monopolar fu...Hospital wastewater contains complex pollutants,including residual organic dyes and antibiotic-resistant pathogens,posing severe risks to ecosystems and human health.Conventional adsorbents,constrained by monopolar functional groups and limited surface sites,fail to remove both pollutants simultaneously.Here,we report an intelligent responsive polyurethane microsphere adsorbent doped with diallyl dimethylammonium chloride modified carbon nanotubes,termed as PUCD microspheres.The PUCD integrates bipolar adsorption sites,tunable micrometer-scale pores,and a near-infrared(NIR)-triggered in situ capture mechanism within a single platform,which achieves up to 98.3%dye removal,maintains strong adsorption performance across a wide pH range and retains 83.3%efficiency for rhodamine B after five cycles.Notably,the PUCD employs a temperature-responsive phase transition:under NIR irradiation,the microspheres undergo shrinkage,reducing the pore size to generate a‘polymer trap',enabling in situ capture of bacteria with>99%efficiencies for both Staphylococcus aureus and Escherichia coli.By immobilizing live bacteria,the PUCD microspheres substantially reduces the risk of pathogen desorption and toxin release.This promising platform offers a safe,efficient,and single-stage strategy for hospital wastewater purification,enabling the simultaneous elimination of dyes and pathogenic bacteria.展开更多
In order to prevent the emission of NO_(x) from diesel engines during the cold-start period,a NO_(x) adsorption selective catalytic reduction(AdSCR)catalyst was prepared by combining a selective catalytic reduction(SC...In order to prevent the emission of NO_(x) from diesel engines during the cold-start period,a NO_(x) adsorption selective catalytic reduction(AdSCR)catalyst was prepared by combining a selective catalytic reduction(SCR)catalyst with an NO_(x) adsorbent.In this study,CeO_(2)/Al_(2)O_(3)(Ce/Al)was employed as the NO_(x) adsorbent,combined with WO_(3)/CeZrO_(x)(W/CZ)as a promising SCR catalyst,to prepare an AdSCR catalyst.The characterization results demonstrate that the synergistic effects of the combined catalyst significantly enhance the activated oxidation of NO_(x) in comparison to the individual catalysts.The addition of Ce/Al enhances the adsorption of NO_(x) on the catalysts,which is then reduced to N_(2) and H_(2)O by NH_(3) under the action of W/CZ catalysts.The results of the NH_(3)-SCR activity test indicate that an excess of Ce/Al results in a reduction in SCR performance,suggesting that there is a balance between the SCR component and the NO_(x) adsorbent.The optimal combination of 20 wt%Ce/Al+W/CZ(20CA-W/CZ)catalyst demonstrates enhanced NO_(x) adsorption-storage performance while maintaining the exceptional NH_(3)-SCR performance.The NO_(x) complete storage time of the 20CA-W/CZ catalyst is 125 s,which is nearly twice as long as that of the Ce/Al and W/CZ catalysts.Furthermore,the NO_(x) conversion of the 20CA-W/CZ catalyst at low temperatures is approximately 10%higher than that of the W/CZ catalyst.The findings of this study offer a promising s trategy for the design of high-performance AdSCR catalysts in the future.展开更多
Platinum group alloys have an excellent electronic structure for oxidation of alcohols,but the active sites are more susceptible to deactivation by CO adsorbates(CO_(ads)).The precise integration of single-atom and al...Platinum group alloys have an excellent electronic structure for oxidation of alcohols,but the active sites are more susceptible to deactivation by CO adsorbates(CO_(ads)).The precise integration of single-atom and alloy structures is highly attractive for energy conversion but still a challenge.Here,we report an ionexchange coupled in situ reduction strategy to fabricate hollow PtPdTe alloy nanoreactors loaded with atomically dispersed Cu sites(Cu_(SA)/h-PtPdTe NRs).The planted oxyphilic Cu single sites and resulted compressive strains are conductive to modulating the electronic structure of the active sites,which changes the rate-determining step of the reaction while inhibiting the formation of CO_(ads)and modulating the adsorption of intermediates,resulting in the improved activity and stability.Specifically,the obtained Cu_(SA)/h-PtPdTe NRs exhibit an excellent oxidation performance of multiple alcohols,especially for methanol and ethanol,with 8.0 and 10.3 times of the mass activity higher than Pt/C,and the activity could be recovered by refreshing the electrolyte and could be sustained for 72,000 and 36,000 s,respectively.Meanwhile,Cu_(SA)/h-PtPdTe NRs show superior oxidation performance and durability to ethylene glycol and glycerol.This work pioneers the realization of precise modulation of catalytic sites using single atoms and provides an encouraging pathway for the design of efficient and stable electrocatalysts for the oxidation of multiple alcohols,which could broaden the range of options and sources of fuel cells.展开更多
Currently,the solid adsorbents with porous structure have been widely applied in CO_(2)capture.However,the unmodified MgO-ZrO_(2)adsorbents appeared to be low adsorption capacity of CO_(2).The solid adsorbent material...Currently,the solid adsorbents with porous structure have been widely applied in CO_(2)capture.However,the unmodified MgO-ZrO_(2)adsorbents appeared to be low adsorption capacity of CO_(2).The solid adsorbent materials were successfully synthesized by loading TEPA onto the pore MgO/ZrO_(2)carriers in the paper.The pore structure and surface characteristic of the samples were analyzed by using XRD,BET,FT-IR and SEM.The adsorbent materials exhibited microcrystalline state,and the crystallinity of all samples gradually decreased as the increase of TEPA content.The pore structure analysis indicated that the modification of MgO-ZrO_(2)adsorbents with TEPA led to the decrease of the specific surface areas,but the narrow micro-mesopore size distributions ranging from 1.8-12 nm in the adsorbents still were maintained.FT-IR spectrum results further verified the successful loading of TEPA.The adsorption capacity of the adsorbents for CO_(2)were tested by using an adsorption apparatus equipped with gas chromatography.The results indicated that when the TEPA loading reached 50%,the sample exhibited the maximum adsorption value for CO_(2),reaching 4.07 mmol/g under the operation condition of 75℃and atmospheric pressure.This result could be assigned to not only the base active sites but also the coexistence of both micropore and mesopore in the adsorbent.After three cycles tests for CO_(2)capture,the adsorption value of the sample for CO_(2)can also reached 95%of its original adsorption capacity,which verified the excellent cyclic operation stability.展开更多
The novel magnetic sepiolite/Fe_(3)O_(4)/zero-valent iron(nZVI)nanocomposite(nZVI@SepH-Mag)was prepared and used to achieve the removal of Cr(VI)in this work.The nZVI@SepH-Mag composites were characterized by XRD,FTIR...The novel magnetic sepiolite/Fe_(3)O_(4)/zero-valent iron(nZVI)nanocomposite(nZVI@SepH-Mag)was prepared and used to achieve the removal of Cr(VI)in this work.The nZVI@SepH-Mag composites were characterized by XRD,FTIR,BET,SEM and TEM.The characterization results indicated that the structure of the composite consisted of small nanoscale nZVI and magnetite(Mag)particles uniformly anchoring on the surface of acid-activated sepiolite(SepH).Batch experiments were used to analyze the effects of main factors on Cr(VI)removal.A 100%removal efficiency in 60 min and enhanced reaction ratio were reached by the composite comparing other existing materials.The kinetic of the adsorption and possible Cr(VI)removal mechanism of the hybrids were also evaluated and proposed.Based on the removal products identified by Raman,XRD and XPS,a reduction mechanism was proposed.The results indicated that the SepH and Mag can inhibit the agglomeration and enhance the dispersibility of nZVI,and Mag and nZVI displayed good synergetic effects.展开更多
Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some sho...Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some shortcomings because of the low permeability and tightness of shale,complex gas flow behavior of multi-scale gas transport regions and multiple gas transport mechanism superpositions,and complex and variable production regimes of shale gas wells.Recent research has demonstrated the existence of a multi-stage isotope fractionation phenomenon during shale gas production,with the fractionation characteristics of each stage associated with the pore structure,gas in place(GIP),adsorption/desorption,and gas production process.This study presents a new approach for estimating shale gas well production and evaluating the adsorbed/free gas ratio throughout production using isotope fractionation techniques.A reservoir-scale carbon isotope fractionation(CIF)model applicable to the production process of shale gas wells was developed for the first time in this research.In contrast to the traditional model,this model improves production prediction accuracy by simultaneously fitting the gas production rate and δ^(13)C_(1) data and provides a new evaluation method of the adsorbed/free gas ratio during shale gas production.The results indicate that the diffusion and adsorption/desorption properties of rock,bottom-hole flowing pressure(BHP)of gas well,and multi-scale gas transport regions of the reservoir all affect isotope fractionation,with the diffusion and adsorption/desorption parameters of rock having the greatest effect on isotope fractionation being D∗/D,PL,VL,α,and others in that order.We effectively tested the universality of the four-stage isotope fractionation feature and revealed a unique isotope fractionation mechanism caused by the superimposed coupling of multi-scale gas transport regions during shale gas well production.Finally,we applied the established CIF model to a shale gas well in the Sichuan Basin,China,and calculated the estimated ultimate recovery(EUR)of the well to be 3.33×10^(8) m^(3);the adsorbed gas ratio during shale gas production was 1.65%,10.03%,and 23.44%in the first,fifth,and tenth years,respectively.The findings are significant for understanding the isotope fractionation mechanism during natural gas transport in complex systems and for formulating and optimizing unconventional natural gas development strategies.展开更多
This paper demonstrates the strategic molecular design of functional polymer monoliths comprised of mesoporous fibers with stimuli-responsive Joule-heating properties for the rapid and efficient recovery of viscous fu...This paper demonstrates the strategic molecular design of functional polymer monoliths comprised of mesoporous fibers with stimuli-responsive Joule-heating properties for the rapid and efficient recovery of viscous fuel oil from water.The mesoporous fibers were composed of carefully selected monomers,which spontaneously entangled with each other to form a spongy monolith in a one-pot synthesis process.The subsequent addition of polypyrrole nanoparticles to the polymer produced superwettable intertwined fibers with strain-responsive conductivity,allowing the monolith to be used as a compressible,fibrous,and porous adsorbent with a high-flux separation capability and a tunable electrical heating effect.This adsorbent was demonstrated to successfully separate different types of low-viscosity oil from water in a continuous,highly efficient process.It also induced a rapid increase in the temperature during the recovery of marine fuel oil(MFO380),with a minimal compression of 3%under an external voltage.The proposed adsorbent can thus be used for the effective recovery of various fuel oils and improved further by incorporating other synergistic components for various water-treatment systems.展开更多
Lead(Pb)is a toxic metal found in wastewater,posing significant health risks to both humans and the environment.This study aimed to develop a novel adsorbent for lead removal from aqueous solutions.This adsorbent,a co...Lead(Pb)is a toxic metal found in wastewater,posing significant health risks to both humans and the environment.This study aimed to develop a novel adsorbent for lead removal from aqueous solutions.This adsorbent,a coffee husk extract-capped magnetite with pumice silica nanocomposite(CHE-capped M/PU/Si-NC),was synthesized using a completely green approach.The novelty of this study lies in the green synthesis of silica nanoparticles(SiO_(2)-NPs)throughout the process.Coffee husk extract(CHE)served as both a stabilizing and capping agent for the SiO_(2)-NPs,which were synthesized from sodium silicate(Na_(2)SiO_(3))extracted from bagasse ash(BA).Subsequently,the CHE-capped silica was co-precipitated with phyto-fabricated magnetite and integrated into a pumice matrix to produce the final CHE-capped M/PU/Si-NC adsorbent.The CHE-capped M/PU/Si-NC was characterized using SEM,XRF,FTIR,BET,XRD,TGA,and zeta potential analysis.The surface area of the CHE-capped M/PU/Si-NC was determined to be 313 m^(2)·g^(-1),and TGA results indicated good thermal stability up to 690℃.The zeta potential was measured at-37.7 mV.XRD analysis of CHE-capped M/PU/Si-NC confirmed the formation of magnetite and revealed its crystal structure.The maximum adsorption performance of this material was observed to be 95%at an adsorbent dosage of 2 g·L^(-1) and an initial Pb^(2+)concentration of 100 g·L^(-1).The adsorption kinetics were best described by the pseudo-second-order kinetic model.The Langmuir isotherm provided a good fit with a maximum adsorption capacity of 150 mg·g^(-1)(R^(2)=0.99).Regeneration studies demonstrated that the adsorbent maintained its high Pb^(2+) uptake capacity for up to five cycles.Overall,these findings suggest that this adsorbent is a promising candidate for the removal of Pb^(2+) from water and wastewater.展开更多
Boron adsorbents with high adsorption capacities have long been a focus of research for a long time.This study used small molecular polyols with different hydroxyl groups as functional monomers and as end-capping agen...Boron adsorbents with high adsorption capacities have long been a focus of research for a long time.This study used small molecular polyols with different hydroxyl groups as functional monomers and as end-capping agents,functional dendritic polyurethanes with nano structure were successfully prepared by one-pot method.The single molecule size and surface morphology were characterized by dynamic light scattering,transmission electron microscopy and scanning electron microscopy,and the molecular size in the dry state was 11 to 18 nm.The prepared materials were used as the boron adsorbents,and the effects of pH,time,boron solution concentration and temperature on the adsorption were studied.The results showed that the capacity of adsorbed boron could reach 110-130 mg·g^(-1).Adsorption was a homogeneous monolayer adsorption controlled by chemisorption,and adsorption thermodynamics showed that was a spontaneous endothermic process.Adsorption behavior was best described by the pseudo-second-order kinetic model and the Langmuir isotherm.This study also showed that it was difficult for ortho/meta-hydroxyl groups to chelate with H_(3)BO_(3) and other polyborates,and the chelates mainly had good chelating properties with B(OH)_(4)^(-),and the chelates formed had large steric hindrance.At the same time,increasing the number of hydroxyl groups of functional monomers was beneficial to increase the adsorption capacity of materials.In addition,the cyclic adsorption/desorption experiments showed that DPUs have good cyclic stability.At the same time,the adsorption results of the original salt lake brine showed that other metal ions in the brine had little effect on the adsorption of boron,and the adsorption capacity was as high as52.93 mg·g^(-1),and the maximum adsorption capacity was obtained by Adams-Bohart model to58.80 mg·g^(-1).The outstanding selectivity and adsorption capacity of these materials have broad potential application,and are expected to be used for the efficient adsorption and removal in boroncontaining water bodies.展开更多
Per-and polyfluoroalkyl substances(PFAS)are persistent environmental contaminants that often show an adverse impact on human health.Rational design of porous adsorbents for selective and reversible removal of PFAS,suc...Per-and polyfluoroalkyl substances(PFAS)are persistent environmental contaminants that often show an adverse impact on human health.Rational design of porous adsorbents for selective and reversible removal of PFAS,such as perfluorooctane sulfonate(PFOS),is imperative and challenging.Herein,a Janus strategy based on an ionic covalent organic framework(iCOF-DGCl)composed of the alternately hydrophobic aromatic domains and hydrophilic guanidinium moieites has been proposed to meet the requirement of high-performance adsorbents.iCOF-DGCl shows fast adsorption kinetics(970.9 mg g^(−1)min^(−1))and ultrahigh uptake capacity(2491 mg g^(−1))toward PFOS,making it one of the most effective materials among the reported PFOS adsorbents.Moreover,the PFOS removal by iCOF-DGCl remains highly selective in the presence of disturbing anions,and the adsorbent could be well recovered for reuse.Mechanism studies have demonstrated that the Janus structure units of iCOF-DGCl form both hydrophobic and electrostatic interactions with the amphiphilic PFOS,thus achieving cooperative adsorption of PFOS.This work provides a facile approach based on Janus structure of COFs adsorbent for wastewater remediation.展开更多
The manufacture and obsolescence of smartphones produce numerous waste plastic accessories(e.g.,waste smartphone protective film(WSPF)),possessing immense potential for recycling.However,available recycling technologi...The manufacture and obsolescence of smartphones produce numerous waste plastic accessories(e.g.,waste smartphone protective film(WSPF)),possessing immense potential for recycling.However,available recycling technologies have limitations such as substrate damage and secondary pollutant generation.The present study aimed to develop a green disposal method that not only recycled polyethylene terephthalate(PET)from WSPF,but also reused the stripped polyacrylate(PAA)adhesive as an adsorbent to reduce solid waste generation.When the WSPF was treated in 1 mol/L NaOH solution at 90°C,the PAA hydrolyzed to two main by-products of 1-butanol and 2-ethylhexanol,weakening the binding strength between PAA and PET and then efficient separation of them.Further bench-scale test revealed that over 97.2%of detachment efficiency toward PAA was achieved during continuous treatment of 17 batches of WSPF(200 g for each)without supplement of NaOH and generation of wastewater.Meanwhile,the economic evaluation indicated that the recycling method would generate a net profit margin of 647%for the second year without considering the incurrence of new cost and input.Additionally,the pyrolysis of waste PAA enabled its conversion into potential adsorbent,which showed 2 to 4 times enhanced adsorption capacity toward styrene and ethyl acetate after modification with NaOH solution.This study provides a green method for recycling waste plastics and inspires a referable solution for solid waste treatment in the smartphone industry.展开更多
文摘Characterization of electric properties of nanomaterials usually involves fabricating field effect transistors （FET） and deriving materials properties from device performances. However, the quality of electrode contacts in FET devices heavily influences the device performance, which makes it difficult to obtain the intrinsic electric properties of nanomaterials. Dielectric force microscopy （DFM）, a contactless method developed recently, can detect the low-frequency dielectric responses of nanomaterials without electric contact, which avoids the influence of electric contact and can be used to study the intrinsic conductivity of nanomaterials. Here we study the influences of surface adsorbates on the conductivity of ZnO nanowires （NWs） by using FET and DFM methods. The conductivity of ZnO NW is much larger in N2 atmosphere than that in ambient environment as measured by FET device, which is further proven by DFM measurement that the ZnO NW exhibits larger dielectric response in N2 environment, and the influence of electrode contacts on measurement can be ruled out. Based on these results, it can be concluded that the adsorbates on ZnO NW surface highly influence the conductivity of ZnO NW rather than the electrode contact. This work also verifies the capability of DFM in measuring electric properties of nanomaterials.
基金supported by the Elements Strategy Initiative for Catalysts and Batteries (ESICB)a Grant-in-Aid for Scientific Research (26248003, 15H01042) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan
文摘The mass spectrometry of gold clusters stabilized by poly（N‐vinyl‐2‐pyrrolidone） （Au：PVP） re‐vealed the presence of Cl adsorbates derived from synthetic precursors, mainly on the Au34 and Au43 clusters. Changes in the amount of Cl adsorbates on the Au clusters did not affect the catalytic prop‐erties for the aerobic oxidation of benzyl alcohol, suggesting that the Cl atoms were only weakly bound to the Au clusters. In contrast, the replacement of Cl with Br on the Au34 and Au43 clusters significantly suppressed activity, without any influence on the electronic structure. This result indi‐cated that the Br atoms were strongly bound to the Au clusters and sterically blocked their active sites. The substantial reduction of the catalytic activity by the Br adsorbates suggested that the Au34 and Au43 clusters made a major contribution to the catalytic activity of the Au：PVP.
基金supported by the National Natural Science Foundation of China(no.22372154,21972131).
文摘Despite substantial efforts in developing high-performance catalysts for the oxygen reduction reaction(ORR),the persistent challenge lies in the high onset overpotential of the ORR,and the effect of the elec-trolyte solution cannot be ignored.Consequently,we have systematically investigated the impact of adsorbate species and concentration,as well as solution pH,on the ORR activity on Pt(111)and Pt(poly)electrodes.The results all tend to establish a linear quantitative relationship between the onset potential for ORR and the adsorption equilibrium potential of the adsorbate.This finding indicates the decisive role of adsorbates in the onset potential for ORR,suggesting that the adsorption potential of adsorbates can serve as an intuitive criterion for ORR activity.Additional support for this conclusion is derived from experimental results obtained from the oxygen evolution reaction on Pt(poly)with different adsorbate species and from the hydrogen evolution reaction on Pt(111)with iodine adsorption.We further propose both an empirical equation for the onset potential for ORR and the concept of a potential-regulated adsor-bate shielding effect to elucidate the influence of adsorbates on ORR activity.This study provides new insights into the high onset overpotential of the ORR and offers potential strategies for predicting and enhancingORRactivity inthefuture.
基金supported by the Ministry of Science and Technology(2016YFA0203302)the National Natural Science Foundation of China(21875042,21634003,51573027 and 11227902)+3 种基金Science and Technology Commission of Shanghai Municipality(16JC1400702 and 18QA1400800)Shanghai Municipal Education Commission(2017-01-07-00-07-E00062)Yanchang Petroleum Groupthe Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning。
文摘Developing efficient electrocatalysts for the oxygen evolution reaction(OER)under neutral conditions is important for microbial electrolysis cells(MECs).However,the OER kinetics in neutral electrolytes at present are extremely sluggish,resulting in high overpotentials that greatly limit the energy conversion efficiencies of MECs.Previous studies failed to probe the adsorbates on surface metal sites of catalysts at the atomic scale and elucidate their influence on the catalytic activities,which has impeded the rational design of efficient neutral OER catalysts with optimal surface structures.Here,using in situ transmission electron microscopy(TEM),in situ X-ray photoelectron spectroscopy(XPS)and in situ low-energy ion scattering studies,we have identified,for the first time,that the electrochemically activated adsorbates on surface metal sites play a critical role in boosting the neutral OER activities of Ru-Ir binary oxide(RuxIryO2)catalysts.The adsorbate-activated RuxIryO2on a glassy carbon electrode achieved a low overpotential of 324 m V at10 m A cm-2in neutral electrolyte,with a 36-fold improvement in turnover frequency compared with that of Ir O2benchmark.Upon application in an MEC system,the resulting full cell showed a decreased voltage of 1.8 V,200 m V lower than the best value reported to date,facilitating efficient synthesis of poly(3-hydroxybutyrate)from bioelectrochemical CO_(2)reduction.Density functional theory(DFT)studies revealed that the enhanced OER activity of RuxIryO2catalyst arose from local structural distortion of adjacent adsorbate-covered Ru octahedra at the catalyst surface and the consequently decreased adsorption energies of OER intermediates on Ir active center.
基金supported by the National Natural Science Foundation of China(21706052,22278114)Natural Science Foundation of Henan Province(242300421575).
文摘Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent research has significantly improved the performance of lignin-based hydrogels,suggesting their substantial potential in fields such as biomedicine,environmental science,and agriculture.This paper reviews the process of lignin extraction,systematically introduces synthesis strategies for preparing lignin-based hydrogels,and discusses the current state of research on these hydrogels in biomedical and environmental protection fields.It concludes by identifying the existing challenges in lignin hydrogel research and envisioning future prospects and development trends.
基金supported by the National Natural Science Foundation of China(Nos.52192684,52270136,and U2340214).
文摘Resourceful food waste treatment is essential for promoting the sustainable development of anaerobic digestion and realizing a circular economy.In this study,biogas residue(BR)was used as a feedstock to produce highvalue-added products(gas,tar,and char-derived high-performance adsorbents)using pyrolysis technology(at 400–800℃).CaCO_(3),the major component of ash,significantly improved the quality of the pyrolysis product by decomposing into CO_(2) and CaO.The gasification reaction of CO_(2) with coke generated substantial CO and facilitated the formation of a rich pore structure in the char.CaO improved tar quality by contributing to secondary cracking reactions and reducing water content.The composite material formed exhibited excellent performance in wastewater treatment,with a maximum methylene blue adsorption capacity of 969.30 mg/g.The maximum adsorption of heavy metals Cu^(2+),Pb^(2+),and Cd^(2+)was 175.44,244.93,and 199.50 mg/g,respectively.The ash fraction on the ash-biochar composite material adsorbent surface enhanced pollutant removal by providing an alkaline adsorption environment and more oxygen-based n-π interaction sites.The economic analysis showed that the high value-added products obtained from the pyrolysis of BR make this process more productive than land use.
基金This work was supported by Riset dan Inovasi untuk Indonesia Maju(RIIM)Kompetisi scheme(Grant number:48/II.7/HK/2025)RP ORNM 2025,National Collaborative Research/RiNa(No.499/2023)Penelitian Dosen Pemula grant from the Ministry of Higher Education,Science and Technology,Republic of Indonesia(1483az/IT9.2.1/PT.01.03/2025).
文摘The increasing need for efficient,sustainable,and environmentally friendly adsorbent materials has driven interest in bio-based alternatives.Conventional silica-based adsorbents,while effective,are often brittle and energy-intensive to produce.In contrast,wood offers a renewable and low-energy option with natural porosity suitable for adsorption.This study investigated the fabrication of wood sponge from tropical balsa(Ochroma bicolor)and pulai(Alstonia scholaris)wood through a dual-stage delignification process as a novel bio-based adsorbent.The process involved alkaline treatment using sodium sulfite(Na_(2)SO_(3))and sodium hydroxide(NaOH)at 100℃for 8,9,and 10 h,followed by bleaching process using hydrogen peroxide(H_(2)O_(2))at 100℃for 1,2,and 3 h.The treated samples were then rinsed to neutral pH,frozen at−20℃for 24 h,and freeze-dried at−50℃for 48 h.The results revealed a notable reduction in density and specific gravity,accompanied by increased weight loss and pore diameter size with prolonged delignification process.Optical changes showed increased translucency and layered structures,particularly in balsa wood.FTIR analysis confirmed a reduction in lignin and hemicellulose content,validating the chemical modification within the treated samples.The resulting wood sponges exhibited good porosity and adsorption capacity,ranging from 1.3 to 5.7 g/g.The optimal treatment—10 h of alkaline delignification followed by 3 h of H_(2)O_(2)bleaching—demonstrated the highest performance,highlighting the potential of tropical wood species as efficient,biodegradable,and eco-friendly adsorbent materials.
基金supported by the National Natural Science Foundation of China grant nos.52470149(P.H.Shao)and 52125002(X.B.Luo)the National Key Research and Development Program of China grant no.2023YFC3905903(P.H.Shao)Nanchang Hangkong University Doctoral Start-up Fund grant no.EA202502100(Y.Y.Zhou).
文摘Selective extraction of precious metals from urban mines plays a crucial role in mitigating the risk of depletion of precious metal resources and reducing waste pollution.However,a major obstacle in precious metal extraction lies in the difficulty of distinguishing the subtle differences in the physicochemical characteristics between them,especially gold and palladium.Herein,a proton-driven separation system was presented for cascade recovery of gold and palladium from waste-printed circuit boards(W-PCBs)leachate using poly(amidoxime)(PAO)hydrogel.This exhibits an ultra-high capacity,extra-fast rate,and excellent selectivity for the extraction of Au(Ⅲ)and Pd(Ⅱ).Notably,the separation of Au(Ⅲ)and Pd(Ⅱ)can be achieved with high selectivity at pH=0,resulting in a remarkable separation factor of k_(Au(Ⅲ)/Pd(Ⅱ))=36.5.This was demonstrated to originate from the differential mechanism of PAO hydrogel for the capture of Au(Ⅲ)and Pd(Ⅱ)under proton-mediated conditions.Drawing inspiration from the mechanism,the proton-driven cascade recovery system demonstrates remarkable efficiency in sequentially recovering 99.92%of gold and 99.05%of palladium from W-PCBs acid leachate.This research opens up a strategy to precisely separate and recover precious metals from e-waste of urban mines.
基金financial support from MICIU/AEI/10.13039/501100011033by the European Union,and grant MOE-T2EP10222-0007 from the Ministry of Education,Singapore。
文摘Density functional theory(DFT)has helped propel the advance of electrocatalysis in the past two decades.In view of its massive use,it is worth asking how reliable DFT is for the prediction of adsorption energies,which are paramount in computational electrocatalysis models.Here,we provide an experimental-computational approach to break down overall adsorption-energy errors into separate gas-phase and adsorbed-phase contributions.The method is evaluated using experimental data and various exchange-correlation functionals and materials for C-and O-containing species.Our main conclusion is that no functional is simultaneously accurate for adsorbates and molecules,as adsorbed-phase errors are visibly different from gas-phase errors.Importantly,total,gas-phase,and adsorbed-phase errors are correlated,revealing intrinsic DFT limitations and enabling the elaboration of swift correction routines.To illustrate the benefits of our approach,we deconvolute and correct all errors in CO_(2)electroreduction to CO and find an agreement with experiments close to chemical accuracy for numerous transition-metal electrodes and all scrutinized functionals.
基金financially supported by the National Natural Science Foundation of China(Nos.52473139 and U21A2098)。
文摘Hospital wastewater contains complex pollutants,including residual organic dyes and antibiotic-resistant pathogens,posing severe risks to ecosystems and human health.Conventional adsorbents,constrained by monopolar functional groups and limited surface sites,fail to remove both pollutants simultaneously.Here,we report an intelligent responsive polyurethane microsphere adsorbent doped with diallyl dimethylammonium chloride modified carbon nanotubes,termed as PUCD microspheres.The PUCD integrates bipolar adsorption sites,tunable micrometer-scale pores,and a near-infrared(NIR)-triggered in situ capture mechanism within a single platform,which achieves up to 98.3%dye removal,maintains strong adsorption performance across a wide pH range and retains 83.3%efficiency for rhodamine B after five cycles.Notably,the PUCD employs a temperature-responsive phase transition:under NIR irradiation,the microspheres undergo shrinkage,reducing the pore size to generate a‘polymer trap',enabling in situ capture of bacteria with>99%efficiencies for both Staphylococcus aureus and Escherichia coli.By immobilizing live bacteria,the PUCD microspheres substantially reduces the risk of pathogen desorption and toxin release.This promising platform offers a safe,efficient,and single-stage strategy for hospital wastewater purification,enabling the simultaneous elimination of dyes and pathogenic bacteria.
基金Project supported by the National Natural Science Foundation of China(22072098)the Sichuan Science and Technology Program(2022ZHCG0125)。
文摘In order to prevent the emission of NO_(x) from diesel engines during the cold-start period,a NO_(x) adsorption selective catalytic reduction(AdSCR)catalyst was prepared by combining a selective catalytic reduction(SCR)catalyst with an NO_(x) adsorbent.In this study,CeO_(2)/Al_(2)O_(3)(Ce/Al)was employed as the NO_(x) adsorbent,combined with WO_(3)/CeZrO_(x)(W/CZ)as a promising SCR catalyst,to prepare an AdSCR catalyst.The characterization results demonstrate that the synergistic effects of the combined catalyst significantly enhance the activated oxidation of NO_(x) in comparison to the individual catalysts.The addition of Ce/Al enhances the adsorption of NO_(x) on the catalysts,which is then reduced to N_(2) and H_(2)O by NH_(3) under the action of W/CZ catalysts.The results of the NH_(3)-SCR activity test indicate that an excess of Ce/Al results in a reduction in SCR performance,suggesting that there is a balance between the SCR component and the NO_(x) adsorbent.The optimal combination of 20 wt%Ce/Al+W/CZ(20CA-W/CZ)catalyst demonstrates enhanced NO_(x) adsorption-storage performance while maintaining the exceptional NH_(3)-SCR performance.The NO_(x) complete storage time of the 20CA-W/CZ catalyst is 125 s,which is nearly twice as long as that of the Ce/Al and W/CZ catalysts.Furthermore,the NO_(x) conversion of the 20CA-W/CZ catalyst at low temperatures is approximately 10%higher than that of the W/CZ catalyst.The findings of this study offer a promising s trategy for the design of high-performance AdSCR catalysts in the future.
基金supported by the National Natural Science Foundation of China(22102132)the Funds for Basic Scientific Research in Central Universities+2 种基金the Scientific Research Foundation of Qingdao UniversityTaishan Scholar Program(NO.tsqnz20231213)sponsored by the Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(CX2024101)。
文摘Platinum group alloys have an excellent electronic structure for oxidation of alcohols,but the active sites are more susceptible to deactivation by CO adsorbates(CO_(ads)).The precise integration of single-atom and alloy structures is highly attractive for energy conversion but still a challenge.Here,we report an ionexchange coupled in situ reduction strategy to fabricate hollow PtPdTe alloy nanoreactors loaded with atomically dispersed Cu sites(Cu_(SA)/h-PtPdTe NRs).The planted oxyphilic Cu single sites and resulted compressive strains are conductive to modulating the electronic structure of the active sites,which changes the rate-determining step of the reaction while inhibiting the formation of CO_(ads)and modulating the adsorption of intermediates,resulting in the improved activity and stability.Specifically,the obtained Cu_(SA)/h-PtPdTe NRs exhibit an excellent oxidation performance of multiple alcohols,especially for methanol and ethanol,with 8.0 and 10.3 times of the mass activity higher than Pt/C,and the activity could be recovered by refreshing the electrolyte and could be sustained for 72,000 and 36,000 s,respectively.Meanwhile,Cu_(SA)/h-PtPdTe NRs show superior oxidation performance and durability to ethylene glycol and glycerol.This work pioneers the realization of precise modulation of catalytic sites using single atoms and provides an encouraging pathway for the design of efficient and stable electrocatalysts for the oxidation of multiple alcohols,which could broaden the range of options and sources of fuel cells.
基金supported by Shanxi Provincial Key Research and Development Project(202102090301026)Graduate Education Innovation Project of Taiyuan University of Science and Technology(SY2023024)。
文摘Currently,the solid adsorbents with porous structure have been widely applied in CO_(2)capture.However,the unmodified MgO-ZrO_(2)adsorbents appeared to be low adsorption capacity of CO_(2).The solid adsorbent materials were successfully synthesized by loading TEPA onto the pore MgO/ZrO_(2)carriers in the paper.The pore structure and surface characteristic of the samples were analyzed by using XRD,BET,FT-IR and SEM.The adsorbent materials exhibited microcrystalline state,and the crystallinity of all samples gradually decreased as the increase of TEPA content.The pore structure analysis indicated that the modification of MgO-ZrO_(2)adsorbents with TEPA led to the decrease of the specific surface areas,but the narrow micro-mesopore size distributions ranging from 1.8-12 nm in the adsorbents still were maintained.FT-IR spectrum results further verified the successful loading of TEPA.The adsorption capacity of the adsorbents for CO_(2)were tested by using an adsorption apparatus equipped with gas chromatography.The results indicated that when the TEPA loading reached 50%,the sample exhibited the maximum adsorption value for CO_(2),reaching 4.07 mmol/g under the operation condition of 75℃and atmospheric pressure.This result could be assigned to not only the base active sites but also the coexistence of both micropore and mesopore in the adsorbent.After three cycles tests for CO_(2)capture,the adsorption value of the sample for CO_(2)can also reached 95%of its original adsorption capacity,which verified the excellent cyclic operation stability.
基金Projects(52474138,52104261,52525401)supported by the National Natural Science Foundation of ChinaProject supported by the New Cornerstone Science Foundation through the XPLORER PRIZE,ChinaProject supported by the Shanxi Key Laboratory Funds of Mine Rock Strata Control and Disaster Prevention,China。
文摘The novel magnetic sepiolite/Fe_(3)O_(4)/zero-valent iron(nZVI)nanocomposite(nZVI@SepH-Mag)was prepared and used to achieve the removal of Cr(VI)in this work.The nZVI@SepH-Mag composites were characterized by XRD,FTIR,BET,SEM and TEM.The characterization results indicated that the structure of the composite consisted of small nanoscale nZVI and magnetite(Mag)particles uniformly anchoring on the surface of acid-activated sepiolite(SepH).Batch experiments were used to analyze the effects of main factors on Cr(VI)removal.A 100%removal efficiency in 60 min and enhanced reaction ratio were reached by the composite comparing other existing materials.The kinetic of the adsorption and possible Cr(VI)removal mechanism of the hybrids were also evaluated and proposed.Based on the removal products identified by Raman,XRD and XPS,a reduction mechanism was proposed.The results indicated that the SepH and Mag can inhibit the agglomeration and enhance the dispersibility of nZVI,and Mag and nZVI displayed good synergetic effects.
基金supported by the Natural Science Foundation of China(Grant No.42302170)National Postdoctoral Innovative Talent Support Program(Grant No.BX20220062)+3 种基金CNPC Innovation Found(Grant No.2022DQ02-0104)National Science Foundation of Heilongjiang Province of China(Grant No.YQ2023D001)Postdoctoral Science Foundation of Heilongjiang Province of China(Grant No.LBH-Z22091)the Natural Science Foundation of Shandong Province(Grant No.ZR2022YQ30).
文摘Prediction of production decline and evaluation of the adsorbed/free gas ratio are critical for determining the lifespan and production status of shale gas wells.Traditional production prediction methods have some shortcomings because of the low permeability and tightness of shale,complex gas flow behavior of multi-scale gas transport regions and multiple gas transport mechanism superpositions,and complex and variable production regimes of shale gas wells.Recent research has demonstrated the existence of a multi-stage isotope fractionation phenomenon during shale gas production,with the fractionation characteristics of each stage associated with the pore structure,gas in place(GIP),adsorption/desorption,and gas production process.This study presents a new approach for estimating shale gas well production and evaluating the adsorbed/free gas ratio throughout production using isotope fractionation techniques.A reservoir-scale carbon isotope fractionation(CIF)model applicable to the production process of shale gas wells was developed for the first time in this research.In contrast to the traditional model,this model improves production prediction accuracy by simultaneously fitting the gas production rate and δ^(13)C_(1) data and provides a new evaluation method of the adsorbed/free gas ratio during shale gas production.The results indicate that the diffusion and adsorption/desorption properties of rock,bottom-hole flowing pressure(BHP)of gas well,and multi-scale gas transport regions of the reservoir all affect isotope fractionation,with the diffusion and adsorption/desorption parameters of rock having the greatest effect on isotope fractionation being D∗/D,PL,VL,α,and others in that order.We effectively tested the universality of the four-stage isotope fractionation feature and revealed a unique isotope fractionation mechanism caused by the superimposed coupling of multi-scale gas transport regions during shale gas well production.Finally,we applied the established CIF model to a shale gas well in the Sichuan Basin,China,and calculated the estimated ultimate recovery(EUR)of the well to be 3.33×10^(8) m^(3);the adsorbed gas ratio during shale gas production was 1.65%,10.03%,and 23.44%in the first,fifth,and tenth years,respectively.The findings are significant for understanding the isotope fractionation mechanism during natural gas transport in complex systems and for formulating and optimizing unconventional natural gas development strategies.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(no.2022R1C1C1003149 and 2020R1A5A8018367)by the Korea Institute of Marine Science&Technology Promotion(KIMST)funded by the Ministry of Oceans and Fisheries,Korea(00254781)This research was alsosupported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(no.RS-202400345266)。
文摘This paper demonstrates the strategic molecular design of functional polymer monoliths comprised of mesoporous fibers with stimuli-responsive Joule-heating properties for the rapid and efficient recovery of viscous fuel oil from water.The mesoporous fibers were composed of carefully selected monomers,which spontaneously entangled with each other to form a spongy monolith in a one-pot synthesis process.The subsequent addition of polypyrrole nanoparticles to the polymer produced superwettable intertwined fibers with strain-responsive conductivity,allowing the monolith to be used as a compressible,fibrous,and porous adsorbent with a high-flux separation capability and a tunable electrical heating effect.This adsorbent was demonstrated to successfully separate different types of low-viscosity oil from water in a continuous,highly efficient process.It also induced a rapid increase in the temperature during the recovery of marine fuel oil(MFO380),with a minimal compression of 3%under an external voltage.The proposed adsorbent can thus be used for the effective recovery of various fuel oils and improved further by incorporating other synergistic components for various water-treatment systems.
文摘Lead(Pb)is a toxic metal found in wastewater,posing significant health risks to both humans and the environment.This study aimed to develop a novel adsorbent for lead removal from aqueous solutions.This adsorbent,a coffee husk extract-capped magnetite with pumice silica nanocomposite(CHE-capped M/PU/Si-NC),was synthesized using a completely green approach.The novelty of this study lies in the green synthesis of silica nanoparticles(SiO_(2)-NPs)throughout the process.Coffee husk extract(CHE)served as both a stabilizing and capping agent for the SiO_(2)-NPs,which were synthesized from sodium silicate(Na_(2)SiO_(3))extracted from bagasse ash(BA).Subsequently,the CHE-capped silica was co-precipitated with phyto-fabricated magnetite and integrated into a pumice matrix to produce the final CHE-capped M/PU/Si-NC adsorbent.The CHE-capped M/PU/Si-NC was characterized using SEM,XRF,FTIR,BET,XRD,TGA,and zeta potential analysis.The surface area of the CHE-capped M/PU/Si-NC was determined to be 313 m^(2)·g^(-1),and TGA results indicated good thermal stability up to 690℃.The zeta potential was measured at-37.7 mV.XRD analysis of CHE-capped M/PU/Si-NC confirmed the formation of magnetite and revealed its crystal structure.The maximum adsorption performance of this material was observed to be 95%at an adsorbent dosage of 2 g·L^(-1) and an initial Pb^(2+)concentration of 100 g·L^(-1).The adsorption kinetics were best described by the pseudo-second-order kinetic model.The Langmuir isotherm provided a good fit with a maximum adsorption capacity of 150 mg·g^(-1)(R^(2)=0.99).Regeneration studies demonstrated that the adsorbent maintained its high Pb^(2+) uptake capacity for up to five cycles.Overall,these findings suggest that this adsorbent is a promising candidate for the removal of Pb^(2+) from water and wastewater.
基金financially supported by Applied Basic Research Project of Qinghai province(2023-ZJ-774)。
文摘Boron adsorbents with high adsorption capacities have long been a focus of research for a long time.This study used small molecular polyols with different hydroxyl groups as functional monomers and as end-capping agents,functional dendritic polyurethanes with nano structure were successfully prepared by one-pot method.The single molecule size and surface morphology were characterized by dynamic light scattering,transmission electron microscopy and scanning electron microscopy,and the molecular size in the dry state was 11 to 18 nm.The prepared materials were used as the boron adsorbents,and the effects of pH,time,boron solution concentration and temperature on the adsorption were studied.The results showed that the capacity of adsorbed boron could reach 110-130 mg·g^(-1).Adsorption was a homogeneous monolayer adsorption controlled by chemisorption,and adsorption thermodynamics showed that was a spontaneous endothermic process.Adsorption behavior was best described by the pseudo-second-order kinetic model and the Langmuir isotherm.This study also showed that it was difficult for ortho/meta-hydroxyl groups to chelate with H_(3)BO_(3) and other polyborates,and the chelates mainly had good chelating properties with B(OH)_(4)^(-),and the chelates formed had large steric hindrance.At the same time,increasing the number of hydroxyl groups of functional monomers was beneficial to increase the adsorption capacity of materials.In addition,the cyclic adsorption/desorption experiments showed that DPUs have good cyclic stability.At the same time,the adsorption results of the original salt lake brine showed that other metal ions in the brine had little effect on the adsorption of boron,and the adsorption capacity was as high as52.93 mg·g^(-1),and the maximum adsorption capacity was obtained by Adams-Bohart model to58.80 mg·g^(-1).The outstanding selectivity and adsorption capacity of these materials have broad potential application,and are expected to be used for the efficient adsorption and removal in boroncontaining water bodies.
基金the financial support from National Key Research and Development Program(2019YFA0210403)National Natural Science Foundation of China(22001178,21975259)+1 种基金Natural Science Foundation of Hebei Province(B2021202077,B2022202039,C20220313)S&T Program of Hebei(236Z4308G).The authors extend their gratitude to Shiyanjia Lab(www.shiyanjia.com)for XPS measurement.
文摘Per-and polyfluoroalkyl substances(PFAS)are persistent environmental contaminants that often show an adverse impact on human health.Rational design of porous adsorbents for selective and reversible removal of PFAS,such as perfluorooctane sulfonate(PFOS),is imperative and challenging.Herein,a Janus strategy based on an ionic covalent organic framework(iCOF-DGCl)composed of the alternately hydrophobic aromatic domains and hydrophilic guanidinium moieites has been proposed to meet the requirement of high-performance adsorbents.iCOF-DGCl shows fast adsorption kinetics(970.9 mg g^(−1)min^(−1))and ultrahigh uptake capacity(2491 mg g^(−1))toward PFOS,making it one of the most effective materials among the reported PFOS adsorbents.Moreover,the PFOS removal by iCOF-DGCl remains highly selective in the presence of disturbing anions,and the adsorbent could be well recovered for reuse.Mechanism studies have demonstrated that the Janus structure units of iCOF-DGCl form both hydrophobic and electrostatic interactions with the amphiphilic PFOS,thus achieving cooperative adsorption of PFOS.This work provides a facile approach based on Janus structure of COFs adsorbent for wastewater remediation.
基金supported by the National Natural Science Foundation of China(No.42177354)Guangzhou Basic and Applied Basic Research Scheme(No.2024A04J6358)the National Key R&D Program of China(No.2019YFC0214402).
文摘The manufacture and obsolescence of smartphones produce numerous waste plastic accessories(e.g.,waste smartphone protective film(WSPF)),possessing immense potential for recycling.However,available recycling technologies have limitations such as substrate damage and secondary pollutant generation.The present study aimed to develop a green disposal method that not only recycled polyethylene terephthalate(PET)from WSPF,but also reused the stripped polyacrylate(PAA)adhesive as an adsorbent to reduce solid waste generation.When the WSPF was treated in 1 mol/L NaOH solution at 90°C,the PAA hydrolyzed to two main by-products of 1-butanol and 2-ethylhexanol,weakening the binding strength between PAA and PET and then efficient separation of them.Further bench-scale test revealed that over 97.2%of detachment efficiency toward PAA was achieved during continuous treatment of 17 batches of WSPF(200 g for each)without supplement of NaOH and generation of wastewater.Meanwhile,the economic evaluation indicated that the recycling method would generate a net profit margin of 647%for the second year without considering the incurrence of new cost and input.Additionally,the pyrolysis of waste PAA enabled its conversion into potential adsorbent,which showed 2 to 4 times enhanced adsorption capacity toward styrene and ethyl acetate after modification with NaOH solution.This study provides a green method for recycling waste plastics and inspires a referable solution for solid waste treatment in the smartphone industry.
