Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the inte...Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the interface,further growth of hydrate due to the suction of water in the capillary system formed between the wall of the cuvette and the end boundary of the hydrate layer occurs.Most probably,substantial effects on the formation of this capillary system may be caused by variations in reactor wall properties,for example,hydrophobic-hydrophilic balance,roughness,etc.We found,that the rate of CO_(2) hydrate film growth on the surface of the humic acid aqueous solution is 4-fold to lower in comparison with the growth rate on the surface of pure water.We suppose that this is caused by the adsorption of humic acid associates on the surface of hydrate particles and,as a consequence,by the deceleration of the diffusion of dissolved carbon dioxide to the growing hydrate particle.展开更多
The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduct...The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduction pathways for CO_(2)are well explored,the single electron reduction to produce the highly reactive carbon dioxide radical anion(CO_(2)^(·-))remains challenging yet promising for green organic transformations.This review contributes to the field by providing a comprehensive analysis of the mechanisms,materials,and reaction pathways involved in CO_(2)^(·-)generation,focusing on the use of visible-lightdriven photocatalytic materials to circumvent the need for high-energy ultraviolet irradiation.Through a systematic examination of CO_(2)^(·-)production,detection methods,and chemical utilization in photocatalytic carboxylation reactions,this review advances understanding of the chemistry of CO_(2)^(·-)and its applications in sustainable chemical synthesis.In addition,it highlights existing key challenges,such as redox potential limitations,and proposes strategies for scaling up photocatalytic systems to enable practical application.By illuminating the pathway to effectively photocatalyze CO_(2)^(·-)generation and its transformative potential in sustainable chemical synthesis,this review equips scientists with critical insights and strategic approaches for overcoming current limitations,driving innovation in photocatalytic materials for solar-to-chemical energy conversion.展开更多
Dimensionality has great influence on the photo/electro-catalysts properties of covalent organic frameworks(COFs) because of the different electronic and porous structures.However,very rare attention has been paid on ...Dimensionality has great influence on the photo/electro-catalysts properties of covalent organic frameworks(COFs) because of the different electronic and porous structures.However,very rare attention has been paid on the dimensionality and function correlations of COF materials.In the present work,one new two-dimensional phthalocyanine COF,namely 2D-NiPc-COF,and one new three-dimensional phthalocyanine COF,namely 3D-NiPc-COF,were fabricated according to the imide reaction between tetraanhydrides of 2,3,9,10,16,17,23,24-octacarboxyphthalocyaninato nickel(Ⅱ) with [2,2-bipyridine]-5,5-diamine and tetrakis(4-aminophenyl) methane,respectively.The crystalline structures of both COFs are verified by the powder X-ray diffraction analysis,computational simulation,and high resolution transmission electron microscopy measurement.Notably,3D-NiPc-COF with dispersed conjugated modules has high utilization efficiency of NiPc electroactive sites of 26.8%,almost two times higher than the in-plane stacking2D-NiPc-COF measured by electrochemical measurement,in turn resulting in its superior electrocatalytic performance with high CO_(2)-to-CO Faradaic efficiency over 90% in a wide potential window,a large partial CO current density of-13.97 mA/cm^(2) at-0.9 V(vs.reversible hydrogen electrode) to 2D-NiPc-COF.Moreover,3D-NiPc-COF has higher turnover number and turnover frequency of 5741.6 and 0.18 s^(-1) at-0.8 V during 8 h lasting measurement.The present work provides an example for the investigation on the correlation between dimensionality and electrochemical properties of 2D and 3D phthalocyanine COFs.展开更多
Sepsis management has significantly improved over the past decades,with intensivists playing a pivotal role in its identification and treatment.[1,2]However,resource constraints in large tertiary hospitals in China li...Sepsis management has significantly improved over the past decades,with intensivists playing a pivotal role in its identification and treatment.[1,2]However,resource constraints in large tertiary hospitals in China limit patient admissions,leading to overcrowding in the emergency departments(EDs)with critically ill patients.[3]This highlights the urgent need for enhanced risk stratification and optimized sepsis management in emergency settings.展开更多
Leveraging the interplay between the metal component and the supporting material represents a cornerstone strategy for augmenting electrocatalytic efficiency,e.g.,electrocatalytic CO_(2)reduction reaction(CO_(2)RR).He...Leveraging the interplay between the metal component and the supporting material represents a cornerstone strategy for augmenting electrocatalytic efficiency,e.g.,electrocatalytic CO_(2)reduction reaction(CO_(2)RR).Herein,we employ freestanding porous carbon fibers(PCNF)as an efficacious and stable support for the uniformly distributed SnO_(2)nanoparticles(SnO_(2)PCNF),thereby capitalizing on the synergistic support effect that arises from their strong interaction.On one hand,the interaction between the SnO_(2)nanoparticles and the carbon support optimizes the electronic configuration of the active centers.This interaction leads to a noteworthy shift of the d-band center toward stronger intermediate adsorption energy,consequently lowering the energy barrier associated with CO_(2)reduction.As a result,the Sn O_(2)PCNF realizes a remarkable CO_(2)RR performance with excellent selectivity towards formate(98.1%).On the other hand,the porous carbon fibers enable the uniform and stable dispersion of SnO_(2)nanoparticles,and this superior porous structure of carbon supports can also facilitate the exposure of the SnO_(2)nanoparticles on the reaction interface to a great extent.Consequently,adequate contact between active sites,reactants,and electrolytes can significantly increase the metal utilization,eventually bringing forth a remarkable7.09 A/mg mass activity.This work might provide a useful idea for improving the utilization rate of metals in numerous electrocatalytic reactions.展开更多
Carbon capture and storage(CCS)is an advanced environmental technology for mitigating CO_(2) emissions and addressing climate change.Among the various approaches,adsorption has emerged as a promising method for CO_(2)...Carbon capture and storage(CCS)is an advanced environmental technology for mitigating CO_(2) emissions and addressing climate change.Among the various approaches,adsorption has emerged as a promising method for CO_(2) capture due to its effiectiveness and practicality.This review explores the potential of clay minerals as adsorbents for CO_(2) capture,providing an in-depth analysis of their inherent properties and the mechanisms involved in adsorption process.The review begins with an introduction to CCS and the concept of adsorption,followed by a detailed examination of various clay minerals,including sepiolite,montmorillonite,bentonite,kaolinite,saponite,halloysite,and illite.Each mineral’s suitability for CO_(2) adsorption is assessed,highlighting the specific properties that contribute to their performance.The mechanisms of CO_(2) adsorption including physisorption,chemisorption,ion exchange,pore diffusion,intraparticle diffusion,surface complexation,and competitive adsorption are thoroughly discussed.The review also covers the modification of clay minerals through physical and chemical treatments,amine functionalization,and composite formation to enhance their CO_(2) adsorption capacity.Additionally,regeneration methods such as temperature-swing adsorption(TSA),pressure-swing adsorption(PSA),and purging are discussed,along with CO_(2) recovery and storage techniques for improving energy efficiency.The review concludes with an overview of characterization methods for clay-based adsorbents and potential applications,while addressing the challenges and future trends in thefield.This work emphasizes the promising role of clay-based adsorbents in advancing CCS technology.展开更多
Through our newly-developed ＂chemical vapor deposition integrated process （ISVD-IP）＇＂ using carbon OlOXlae （t..u2） as me raw matenal and only carbon source introduced, CO2 could be catalytically activated and c...Through our newly-developed ＂chemical vapor deposition integrated process （ISVD-IP）＇＂ using carbon OlOXlae （t..u2） as me raw matenal and only carbon source introduced, CO2 could be catalytically activated and converted to a new solid-form product, i.e., carbon nanotubes （CO2-derived） at a quite high yield （the single-pass carbon yield in the solid-form carbon-product produced from CO2 catalytic capture and conversion was more than 30% at a single-pass carbon-base）. For comparison, when only pure carbon dioxide was introduced using the conventional CVD method without integrated process, no solid-form carbon-material product could be formed. In the addition of saturated steam at room temperature in the feed for CVD, there were much more end-opening carbon nano-tubes produced, at a slightly higher carbon yield. These inspiring works opened a remarkable and alternative new approach for carbon dioxide catalytic capture to solid-form product, comparing with that of CO2 sequestration （CCS） or CO2 mineralization （solidification）, etc. As a result, there was much less body volume and almost no greenhouse effect for this solid-form carbon-material than those of primitive carbon dioxide.展开更多
A series of gluscose derivatives were designed, synthesized, and their structures were confirmed by IR, NMR and elementary analysis. All new compounds are highly soluble in liquid or supercritical carbon dioxide. The ...A series of gluscose derivatives were designed, synthesized, and their structures were confirmed by IR, NMR and elementary analysis. All new compounds are highly soluble in liquid or supercritical carbon dioxide. The compound with electron-withdrawing substituent on benzene ring had even better solubility than the compounds with electron-donating substituent.展开更多
1 Introduction Nowadays, green chemistry has received increased attention. The use of water and scCO2 as a solvent or reagent is an important field for organic reactions and green chemistry both in laboratory and indu...1 Introduction Nowadays, green chemistry has received increased attention. The use of water and scCO2 as a solvent or reagent is an important field for organic reactions and green chemistry both in laboratory and industry.展开更多
Copolymerization of carbon dioxide with epichlorohydrin was successfully carried out by usingNd(P_(204))_3-Al(i-Bu)_3 as catalyst (P_(204))=(RO)_2 POO--,R=CH_3 (CH_2),CH(C_2H_5) CH_2--). Addi-tion of carbonyl compound...Copolymerization of carbon dioxide with epichlorohydrin was successfully carried out by usingNd(P_(204))_3-Al(i-Bu)_3 as catalyst (P_(204))=(RO)_2 POO--,R=CH_3 (CH_2),CH(C_2H_5) CH_2--). Addi-tion of carbonyl compounds into the catalyst decreased the carbon dioxide content of the copoly-mer to some extent. Compared to nonpolar solvents, ethereal and moderate polar solvents werefavourable to obtaining higher carbon dioxide content copolymer. The coincidence of these resultswith the assumed copolymerization scheme clearly indicated that the copolymerization proceeds via coordinate anionic mechanism.展开更多
The catalyzation of CoTPP for electrocarboxylation of alkyl halides, alkenes and ketones with CO_2 are studied. The electrocarboxylation of these organic compounds with CO_2 in the presenec of catalyst can occur at mo...The catalyzation of CoTPP for electrocarboxylation of alkyl halides, alkenes and ketones with CO_2 are studied. The electrocarboxylation of these organic compounds with CO_2 in the presenec of catalyst can occur at more positive potential than that of no catalyst. The products of electrocarboxylation were identified by UV, IR and GC-MS. The electrocarboxylation mechanisms of different organic compounds are discussed.展开更多
Porous carbon microspheres are widely regarded as a superior CO_(2) adsorbent due to their exceptional efficiency and affordability.However,better adsorption performance is very attractive for porous carbon microspher...Porous carbon microspheres are widely regarded as a superior CO_(2) adsorbent due to their exceptional efficiency and affordability.However,better adsorption performance is very attractive for porous carbon microspheres.And modification of the pore structure is one of the effective strategies.In this study,multi-cavity mesoporous carbon microspheres were successfully synthesized by the synergistic method of soft and hard templates,during which a phenolic resin with superior thermal stability was employed as the carbon precursor and a mixture of silica sol and F108 as the mesoporous template.Carbon microspheres with multi-cavity mesoporous structures were prepared,and all the samples showed highly even mesopores,with diameters around 12 nm.The diameter of these microspheres decreased from 396.8 nm to about 182.5 nm with the increase of silica sol.After CO_(2) activation,these novel carbon microspheres(APCF0.5-S1.75)demonstrated high specific surface area(983.3 m^(2)/g)and remarkable CO_(2) uptake of 4.93 mmol/g at 0℃ and1 bar.This could be attributed to the unique multi-cavity structure,which offers uniform mesoporous pore channels,minimal CO_(2) transport of and a greater number of active sites for CO_(2) adsorption.展开更多
Various technologies and projects have been explored and developed for the synergetic control of environmental pollution and carbon emissions in aquatic ecosystems.Planting submerged vegetation in shallow waters was a...Various technologies and projects have been explored and developed for the synergetic control of environmental pollution and carbon emissions in aquatic ecosystems.Planting submerged vegetation in shallow waters was also expected to achieve this purpose.However,the magnitude and mechanism of carbon dioxide(CO_(2))emission affected by submerged vegetation is not clear enough in complex aquatic ecosystems.This study investigated the influences of submerged plants on CO_(2)emission,ecosystem metabolism features,and microbial community traits based on observations in river networks on the Changjiang River Delta.The results showed that CO_(2)emission from planted waters accounted for 73%of unplanted waters.Meanwhile,planted waters had higher dissolved organic carbon removal capacity in overlying water and higher potential of carbon sequestration in sediment at the same time.These distinctions between the two habitats were attributed to(1)improved CO_(2)and bicarbonate consumption in water columns via enhancing photosynthesis and(2)inhibited CO_(2)production by reconstructing the benthic microbial community.Additional eco-advantages were found in planted sediments,such as a high potential of methane oxidation and xenobiotics biodegradation and a low risk of becoming black and odorous.In brief,submerged vegetation is beneficial in promoting pollution removal and carbon retention synchronously.This study advances our understanding of the feedback between aquatic metabolism and CO_(2)emission.展开更多
To improve the efficiency of the carbon dioxide cycling process and to reduce the regeneration energy consumption, a sterically hindered amine of 2-amino-2-methyl-1- propranol （AMP） was investigated to determine its...To improve the efficiency of the carbon dioxide cycling process and to reduce the regeneration energy consumption, a sterically hindered amine of 2-amino-2-methyl-1- propranol （AMP） was investigated to determine its regeneration behavior as a CO2 absorbent. The CO2 absorption and amine regeneration characteristics were experimentally examined under various operating conditions. The regeneration efficiency increased from 86.2% to 98.3% during the temperature range of 358 to 403 K. The most suitable regeneration temperature for AMP was 383 K, in this experiment condition, and the regeneration efficiency of absorption/regeneration runs descended from 98.3% to 94.0%. A number of heat-stable salts （HSS） could cause a reduction in CO2 absorption capacity and regeneration efficiency. The results indicated that aqueous AMP was easier to regenerate with less loss of absorption capacity than other amines, such as, monoethanolamine （MEA）, diethanolamine （DEA）, diethylenetriamine （DETA）, and N-methyldiethanolamine （MDEA）.展开更多
This study investigates the application of carbon dioxide (CO2) sequestration to address challenges in water-drive gas reservoirs, specifically focusing on improving gas recovery and mitigating water invasion. Traditi...This study investigates the application of carbon dioxide (CO2) sequestration to address challenges in water-drive gas reservoirs, specifically focusing on improving gas recovery and mitigating water invasion. Traditional methods like blow-down and co-production have limitations, including sand production, water coning, and inefficiency in strong aquifers. To overcome these issues, this research explores CO2 injection near the edge aquifer, aiming to reduce water influx and enhance gas recovery through the propagation of a CO2 plume in the gas-water contact zone. Both synthetic and real compositional reservoir models were studied, with CO2 injection performed while maintaining reservoir pressure below 90% of the initial level. Results show that CO2 sequestration significantly improved recovery, particularly in higher permeability reservoirs, where it reduced aquifer influx and increased gas production by 26% under challenging conditions. While CO2 dissolution in water decreased aquifer influx by 39%, its adverse effect on sweep efficiency led to a reduction in gas and water production by 4.2% and 10%, respectively. The method's effectiveness was not significantly impacted by aquifer permeability, but it was sensitive to vertical-to-horizontal permeability ratios. When applied to a real gas reservoir, the proposed method increased gas production by 14% compared to conventional techniques, with minimal CO2 production over a 112-year period. This study demonstrates the potential of CO2 sequestration as a comprehensive solution for enhancing gas recovery, reducing water production, and mitigating environmental impacts in water-drive gas reservoirs.展开更多
Although supercritical carbon dioxide(SC-CO_(2))fracturing shows tremendous potential for maximizing injection efficiency and enhancing storage volumes,few investigations have been reported on the SC-CO_(2) fracturing...Although supercritical carbon dioxide(SC-CO_(2))fracturing shows tremendous potential for maximizing injection efficiency and enhancing storage volumes,few investigations have been reported on the SC-CO_(2) fracturing characteristics of tight basalts and the reactions between fractured basalt and SC-CO_(2).In this study,hydraulic fracturing experiments were conducted on cylindrical basalt specimens using water and SC-CO_(2) as fracturing fluids.Geometric parameters were proposed to characterize the fracture morphologies based on the three-dimensional(3D)reconstructions of fracture networks.The rock slices with induced fractures after SC-CO_(2) fracturing were then processed for fluid(deionized water/SC-CO_(2))-basalt reaction tests.The experimental results demonstrate that SC-CO_(2) fracturing can induce complex and tortuous fractures with spatially dispersed morphologies.Other fracturing behaviors accompanying the acoustic emission(AE)signals and pump pressure changes show that the AE activity responds almost simultaneously to variation in the pump pressure.The fractured basalt blocks exposed to both SC-CO_(2) and water exhibit rough and uneven surfaces,along with decreased intensities in the element peaks,indicating that solubility trapping predominantly occurs during the early injection stage.The above findings provide a laboratory research basis for understanding the fracturing and sequestration issues related to effective CO_(2) utilization.展开更多
The Ni-CeO2/Al2O3 catalysts with a nickel content of 15 wt% prepared via impregnating boehmite were found to be highly active and stable for methanation of carbon dioxide with hydrogen at a H2/CO2 molar ratio of 4. Th...The Ni-CeO2/Al2O3 catalysts with a nickel content of 15 wt% prepared via impregnating boehmite were found to be highly active and stable for methanation of carbon dioxide with hydrogen at a H2/CO2 molar ratio of 4. The effects of CeO2 content and reaction temperature on the performance of the Ni-CeO2/Al2O3 catalysts were studied in detail. The results showed that the catalytic performance was strongly dependent on the CeO2 content in Ni-CeO2/Al2O3 catalysts and that the catalysts with 2 wt% CeO2 had the highest catalytic activity among the tested ones at 350 ℃. The XRD and H2-TPR characterizations revealed that the addition of CeO2 decreased the reduction temperature by altering the interaction between Ni and Al2O3, and improved the reducibility of the catalyst. Preliminary stability test of 120 h on stream over the Ni-2CeO2/Al2O3 catalyst at 350 ℃ revealed that the catalyst was much better than the unpromoted one.展开更多
Confinement effect is an effective method to enhance carbon dioxide(CO_(2))solubility.In this study,a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([Hmim][NTf_2])/mesoporous titanium ...Confinement effect is an effective method to enhance carbon dioxide(CO_(2))solubility.In this study,a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([Hmim][NTf_2])/mesoporous titanium dioxide(M-TiO_(2))/water(H_2O)was developed,and its confinement effect was regulated by changing the pore structure of M-TiO_(2).CO_(2) solubility in the hybrid sorbent was measured experimentally,and the thermodynamic properties including Henry's constant and desorption enthalpy were calculated.Furthermore,the confinement effect in the hybrid sorbent was quantified.Additionally,the hybrid sorbent was recycled with a multi-cycle experiment.The results showed that M-TiO_(2) calcined at 773.2 K(MT500)could lead to an efficient confinement effect.CO_(2) solubility in the hybrid sorbent increased by 49.8%compared to that of H_2O when the mass fraction of[Hmim][NTf_2]/MT500 was 5.0%(mass),where the contribution of confinement effect on Gibbs free energy occupied 5.2%.展开更多
The calcium-containing rare earth solution is generated during the recovery processes of NdFeB waste,which is treated as wastewater by enterprises.In this paper,the carbon dioxide carbonization method was applied to t...The calcium-containing rare earth solution is generated during the recovery processes of NdFeB waste,which is treated as wastewater by enterprises.In this paper,the carbon dioxide carbonization method was applied to the separation of rare earths and calcium in the solution,as well as the preparation of rare earth oxides with a large specific surface.It is shown that the process of CO_(2)carbonization of solution includes reactions such as the dissolution,diffusion and ionization of CO_(2),the carbonate precipitation of rare earth ions,and the neutralization of hydrogen ions.At a pH of 4.5,the carbonization precipitation rate is effectively controlled,enabling homogeneous precipitation and ensuring both high precipitation yield and rare earth oxides purity.In this way,the crystallization of carbonization products is a process dominated by the oriented attachment theory and coexisting with the Ostwald ripening theory,resulting in abundant pores formed by multiple layers of stacking in the products.With the optimal carbonization conditions,the rare earth precipitation yield solution reaches 99.32%.The obtained carbonization products are crystalline(LaCe)(CO_(3))_(3)·8H_(2)O,and the purity of the rare earth oxides is as high as 99.22 wt%.The specific surface area of the rare earth oxides reaches 94.7 m^(2)/g,and its adsorption efficiency for tetracycline hydrochloride in solution can reach 92.6%in a short time.The rare earth oxides are expected to be used as an adsorption material for wastewater treatment and other adsorption environments.展开更多
基金supported by the Russian Science Foundation(23-29-00830).
文摘Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the interface,further growth of hydrate due to the suction of water in the capillary system formed between the wall of the cuvette and the end boundary of the hydrate layer occurs.Most probably,substantial effects on the formation of this capillary system may be caused by variations in reactor wall properties,for example,hydrophobic-hydrophilic balance,roughness,etc.We found,that the rate of CO_(2) hydrate film growth on the surface of the humic acid aqueous solution is 4-fold to lower in comparison with the growth rate on the surface of pure water.We suppose that this is caused by the adsorption of humic acid associates on the surface of hydrate particles and,as a consequence,by the deceleration of the diffusion of dissolved carbon dioxide to the growing hydrate particle.
基金funding programs,the Walter Benjamin Programme(DFG,German Research Foundation,project number:530742479)the ProChancecareer Programme for the Promotion of Equal Opportunities in Academia for providing the financial support+1 种基金financial support by the Deutsche Forschungsgemeinschaft via the TRR 234 Cata Light(DFG,German Research Foundation)-Projektnummer 364549901-TRR 234[B6]the financial support taken from the CSIR and UGC,Delhi,India。
文摘The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduction pathways for CO_(2)are well explored,the single electron reduction to produce the highly reactive carbon dioxide radical anion(CO_(2)^(·-))remains challenging yet promising for green organic transformations.This review contributes to the field by providing a comprehensive analysis of the mechanisms,materials,and reaction pathways involved in CO_(2)^(·-)generation,focusing on the use of visible-lightdriven photocatalytic materials to circumvent the need for high-energy ultraviolet irradiation.Through a systematic examination of CO_(2)^(·-)production,detection methods,and chemical utilization in photocatalytic carboxylation reactions,this review advances understanding of the chemistry of CO_(2)^(·-)and its applications in sustainable chemical synthesis.In addition,it highlights existing key challenges,such as redox potential limitations,and proposes strategies for scaling up photocatalytic systems to enable practical application.By illuminating the pathway to effectively photocatalyze CO_(2)^(·-)generation and its transformative potential in sustainable chemical synthesis,this review equips scientists with critical insights and strategic approaches for overcoming current limitations,driving innovation in photocatalytic materials for solar-to-chemical energy conversion.
基金Financial support from the Natural Science Foundation(NSF) of China(Nos.22205015,22175020,and 22235001)the National Postdoctoral Program for Innovative Talents(No.BX20220032)+1 种基金the China Postdoctoral Science Foundation Funded Project(No.2022BG013)the Fundamental Research Funds for the Central Universities(Nos.00007709 and 00007770)。
文摘Dimensionality has great influence on the photo/electro-catalysts properties of covalent organic frameworks(COFs) because of the different electronic and porous structures.However,very rare attention has been paid on the dimensionality and function correlations of COF materials.In the present work,one new two-dimensional phthalocyanine COF,namely 2D-NiPc-COF,and one new three-dimensional phthalocyanine COF,namely 3D-NiPc-COF,were fabricated according to the imide reaction between tetraanhydrides of 2,3,9,10,16,17,23,24-octacarboxyphthalocyaninato nickel(Ⅱ) with [2,2-bipyridine]-5,5-diamine and tetrakis(4-aminophenyl) methane,respectively.The crystalline structures of both COFs are verified by the powder X-ray diffraction analysis,computational simulation,and high resolution transmission electron microscopy measurement.Notably,3D-NiPc-COF with dispersed conjugated modules has high utilization efficiency of NiPc electroactive sites of 26.8%,almost two times higher than the in-plane stacking2D-NiPc-COF measured by electrochemical measurement,in turn resulting in its superior electrocatalytic performance with high CO_(2)-to-CO Faradaic efficiency over 90% in a wide potential window,a large partial CO current density of-13.97 mA/cm^(2) at-0.9 V(vs.reversible hydrogen electrode) to 2D-NiPc-COF.Moreover,3D-NiPc-COF has higher turnover number and turnover frequency of 5741.6 and 0.18 s^(-1) at-0.8 V during 8 h lasting measurement.The present work provides an example for the investigation on the correlation between dimensionality and electrochemical properties of 2D and 3D phthalocyanine COFs.
基金supported by grants from the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(2021-I2M-1-062,to BD).
文摘Sepsis management has significantly improved over the past decades,with intensivists playing a pivotal role in its identification and treatment.[1,2]However,resource constraints in large tertiary hospitals in China limit patient admissions,leading to overcrowding in the emergency departments(EDs)with critically ill patients.[3]This highlights the urgent need for enhanced risk stratification and optimized sepsis management in emergency settings.
基金supported by the National Natural Science Foundation of China(Nos.22172099,U21A20312)Guangdong Basic and Applied Basic Research Foundation(Nos.2023A1515012776,2022B1515120084)the Shenzhen Science and Technology Program(No.RCYX20200714114535052)。
文摘Leveraging the interplay between the metal component and the supporting material represents a cornerstone strategy for augmenting electrocatalytic efficiency,e.g.,electrocatalytic CO_(2)reduction reaction(CO_(2)RR).Herein,we employ freestanding porous carbon fibers(PCNF)as an efficacious and stable support for the uniformly distributed SnO_(2)nanoparticles(SnO_(2)PCNF),thereby capitalizing on the synergistic support effect that arises from their strong interaction.On one hand,the interaction between the SnO_(2)nanoparticles and the carbon support optimizes the electronic configuration of the active centers.This interaction leads to a noteworthy shift of the d-band center toward stronger intermediate adsorption energy,consequently lowering the energy barrier associated with CO_(2)reduction.As a result,the Sn O_(2)PCNF realizes a remarkable CO_(2)RR performance with excellent selectivity towards formate(98.1%).On the other hand,the porous carbon fibers enable the uniform and stable dispersion of SnO_(2)nanoparticles,and this superior porous structure of carbon supports can also facilitate the exposure of the SnO_(2)nanoparticles on the reaction interface to a great extent.Consequently,adequate contact between active sites,reactants,and electrolytes can significantly increase the metal utilization,eventually bringing forth a remarkable7.09 A/mg mass activity.This work might provide a useful idea for improving the utilization rate of metals in numerous electrocatalytic reactions.
文摘Carbon capture and storage(CCS)is an advanced environmental technology for mitigating CO_(2) emissions and addressing climate change.Among the various approaches,adsorption has emerged as a promising method for CO_(2) capture due to its effiectiveness and practicality.This review explores the potential of clay minerals as adsorbents for CO_(2) capture,providing an in-depth analysis of their inherent properties and the mechanisms involved in adsorption process.The review begins with an introduction to CCS and the concept of adsorption,followed by a detailed examination of various clay minerals,including sepiolite,montmorillonite,bentonite,kaolinite,saponite,halloysite,and illite.Each mineral’s suitability for CO_(2) adsorption is assessed,highlighting the specific properties that contribute to their performance.The mechanisms of CO_(2) adsorption including physisorption,chemisorption,ion exchange,pore diffusion,intraparticle diffusion,surface complexation,and competitive adsorption are thoroughly discussed.The review also covers the modification of clay minerals through physical and chemical treatments,amine functionalization,and composite formation to enhance their CO_(2) adsorption capacity.Additionally,regeneration methods such as temperature-swing adsorption(TSA),pressure-swing adsorption(PSA),and purging are discussed,along with CO_(2) recovery and storage techniques for improving energy efficiency.The review concludes with an overview of characterization methods for clay-based adsorbents and potential applications,while addressing the challenges and future trends in thefield.This work emphasizes the promising role of clay-based adsorbents in advancing CCS technology.
基金the National 973 Program of Ministry of Sciences and Technologies of China(2011CB201202)the National Natural Science Foundation of China(20776089)
文摘Through our newly-developed ＂chemical vapor deposition integrated process （ISVD-IP）＇＂ using carbon OlOXlae （t..u2） as me raw matenal and only carbon source introduced, CO2 could be catalytically activated and converted to a new solid-form product, i.e., carbon nanotubes （CO2-derived） at a quite high yield （the single-pass carbon yield in the solid-form carbon-product produced from CO2 catalytic capture and conversion was more than 30% at a single-pass carbon-base）. For comparison, when only pure carbon dioxide was introduced using the conventional CVD method without integrated process, no solid-form carbon-material product could be formed. In the addition of saturated steam at room temperature in the feed for CVD, there were much more end-opening carbon nano-tubes produced, at a slightly higher carbon yield. These inspiring works opened a remarkable and alternative new approach for carbon dioxide catalytic capture to solid-form product, comparing with that of CO2 sequestration （CCS） or CO2 mineralization （solidification）, etc. As a result, there was much less body volume and almost no greenhouse effect for this solid-form carbon-material than those of primitive carbon dioxide.
文摘A series of gluscose derivatives were designed, synthesized, and their structures were confirmed by IR, NMR and elementary analysis. All new compounds are highly soluble in liquid or supercritical carbon dioxide. The compound with electron-withdrawing substituent on benzene ring had even better solubility than the compounds with electron-donating substituent.
基金the National Natural Science Foundation of China(Nos.20332030,20572027,20625205 and 20772034)Natural Science Foundation of Guangdong Province,China(No.07118070).
文摘1 Introduction Nowadays, green chemistry has received increased attention. The use of water and scCO2 as a solvent or reagent is an important field for organic reactions and green chemistry both in laboratory and industry.
文摘Copolymerization of carbon dioxide with epichlorohydrin was successfully carried out by usingNd(P_(204))_3-Al(i-Bu)_3 as catalyst (P_(204))=(RO)_2 POO--,R=CH_3 (CH_2),CH(C_2H_5) CH_2--). Addi-tion of carbonyl compounds into the catalyst decreased the carbon dioxide content of the copoly-mer to some extent. Compared to nonpolar solvents, ethereal and moderate polar solvents werefavourable to obtaining higher carbon dioxide content copolymer. The coincidence of these resultswith the assumed copolymerization scheme clearly indicated that the copolymerization proceeds via coordinate anionic mechanism.
基金This work is supported by the National Natural Science Foundation of China
文摘The catalyzation of CoTPP for electrocarboxylation of alkyl halides, alkenes and ketones with CO_2 are studied. The electrocarboxylation of these organic compounds with CO_2 in the presenec of catalyst can occur at more positive potential than that of no catalyst. The products of electrocarboxylation were identified by UV, IR and GC-MS. The electrocarboxylation mechanisms of different organic compounds are discussed.
基金supported by the National Key R&D Program of China(No.2021YFB3501102).
文摘Porous carbon microspheres are widely regarded as a superior CO_(2) adsorbent due to their exceptional efficiency and affordability.However,better adsorption performance is very attractive for porous carbon microspheres.And modification of the pore structure is one of the effective strategies.In this study,multi-cavity mesoporous carbon microspheres were successfully synthesized by the synergistic method of soft and hard templates,during which a phenolic resin with superior thermal stability was employed as the carbon precursor and a mixture of silica sol and F108 as the mesoporous template.Carbon microspheres with multi-cavity mesoporous structures were prepared,and all the samples showed highly even mesopores,with diameters around 12 nm.The diameter of these microspheres decreased from 396.8 nm to about 182.5 nm with the increase of silica sol.After CO_(2) activation,these novel carbon microspheres(APCF0.5-S1.75)demonstrated high specific surface area(983.3 m^(2)/g)and remarkable CO_(2) uptake of 4.93 mmol/g at 0℃ and1 bar.This could be attributed to the unique multi-cavity structure,which offers uniform mesoporous pore channels,minimal CO_(2) transport of and a greater number of active sites for CO_(2) adsorption.
基金supported by the Youth Exploration Foundation of Chinese Research Academy of Environmental Sciences(No.2022YSKY-55).
文摘Various technologies and projects have been explored and developed for the synergetic control of environmental pollution and carbon emissions in aquatic ecosystems.Planting submerged vegetation in shallow waters was also expected to achieve this purpose.However,the magnitude and mechanism of carbon dioxide(CO_(2))emission affected by submerged vegetation is not clear enough in complex aquatic ecosystems.This study investigated the influences of submerged plants on CO_(2)emission,ecosystem metabolism features,and microbial community traits based on observations in river networks on the Changjiang River Delta.The results showed that CO_(2)emission from planted waters accounted for 73%of unplanted waters.Meanwhile,planted waters had higher dissolved organic carbon removal capacity in overlying water and higher potential of carbon sequestration in sediment at the same time.These distinctions between the two habitats were attributed to(1)improved CO_(2)and bicarbonate consumption in water columns via enhancing photosynthesis and(2)inhibited CO_(2)production by reconstructing the benthic microbial community.Additional eco-advantages were found in planted sediments,such as a high potential of methane oxidation and xenobiotics biodegradation and a low risk of becoming black and odorous.In brief,submerged vegetation is beneficial in promoting pollution removal and carbon retention synchronously.This study advances our understanding of the feedback between aquatic metabolism and CO_(2)emission.
文摘To improve the efficiency of the carbon dioxide cycling process and to reduce the regeneration energy consumption, a sterically hindered amine of 2-amino-2-methyl-1- propranol （AMP） was investigated to determine its regeneration behavior as a CO2 absorbent. The CO2 absorption and amine regeneration characteristics were experimentally examined under various operating conditions. The regeneration efficiency increased from 86.2% to 98.3% during the temperature range of 358 to 403 K. The most suitable regeneration temperature for AMP was 383 K, in this experiment condition, and the regeneration efficiency of absorption/regeneration runs descended from 98.3% to 94.0%. A number of heat-stable salts （HSS） could cause a reduction in CO2 absorption capacity and regeneration efficiency. The results indicated that aqueous AMP was easier to regenerate with less loss of absorption capacity than other amines, such as, monoethanolamine （MEA）, diethanolamine （DEA）, diethylenetriamine （DETA）, and N-methyldiethanolamine （MDEA）.
文摘This study investigates the application of carbon dioxide (CO2) sequestration to address challenges in water-drive gas reservoirs, specifically focusing on improving gas recovery and mitigating water invasion. Traditional methods like blow-down and co-production have limitations, including sand production, water coning, and inefficiency in strong aquifers. To overcome these issues, this research explores CO2 injection near the edge aquifer, aiming to reduce water influx and enhance gas recovery through the propagation of a CO2 plume in the gas-water contact zone. Both synthetic and real compositional reservoir models were studied, with CO2 injection performed while maintaining reservoir pressure below 90% of the initial level. Results show that CO2 sequestration significantly improved recovery, particularly in higher permeability reservoirs, where it reduced aquifer influx and increased gas production by 26% under challenging conditions. While CO2 dissolution in water decreased aquifer influx by 39%, its adverse effect on sweep efficiency led to a reduction in gas and water production by 4.2% and 10%, respectively. The method's effectiveness was not significantly impacted by aquifer permeability, but it was sensitive to vertical-to-horizontal permeability ratios. When applied to a real gas reservoir, the proposed method increased gas production by 14% compared to conventional techniques, with minimal CO2 production over a 112-year period. This study demonstrates the potential of CO2 sequestration as a comprehensive solution for enhancing gas recovery, reducing water production, and mitigating environmental impacts in water-drive gas reservoirs.
基金supported by the National Key Research and Development Project(Grant No.2023YFE0110900)the National Natural Science Foundation of China(Grant No.42320104003)the Shanghai Pujiang Programme(Grant No.23PJD105).
文摘Although supercritical carbon dioxide(SC-CO_(2))fracturing shows tremendous potential for maximizing injection efficiency and enhancing storage volumes,few investigations have been reported on the SC-CO_(2) fracturing characteristics of tight basalts and the reactions between fractured basalt and SC-CO_(2).In this study,hydraulic fracturing experiments were conducted on cylindrical basalt specimens using water and SC-CO_(2) as fracturing fluids.Geometric parameters were proposed to characterize the fracture morphologies based on the three-dimensional(3D)reconstructions of fracture networks.The rock slices with induced fractures after SC-CO_(2) fracturing were then processed for fluid(deionized water/SC-CO_(2))-basalt reaction tests.The experimental results demonstrate that SC-CO_(2) fracturing can induce complex and tortuous fractures with spatially dispersed morphologies.Other fracturing behaviors accompanying the acoustic emission(AE)signals and pump pressure changes show that the AE activity responds almost simultaneously to variation in the pump pressure.The fractured basalt blocks exposed to both SC-CO_(2) and water exhibit rough and uneven surfaces,along with decreased intensities in the element peaks,indicating that solubility trapping predominantly occurs during the early injection stage.The above findings provide a laboratory research basis for understanding the fracturing and sequestration issues related to effective CO_(2) utilization.
基金supported by the National High Technology Research and Development Program of China(Grant No.2006AA11A189)Science and Technology Commission of Shanghai Municipality(Grant No.07DZ12036,and08DZ12064)Shanghai Pujiang Program(Grant No.08PJ1405900)
文摘The Ni-CeO2/Al2O3 catalysts with a nickel content of 15 wt% prepared via impregnating boehmite were found to be highly active and stable for methanation of carbon dioxide with hydrogen at a H2/CO2 molar ratio of 4. The effects of CeO2 content and reaction temperature on the performance of the Ni-CeO2/Al2O3 catalysts were studied in detail. The results showed that the catalytic performance was strongly dependent on the CeO2 content in Ni-CeO2/Al2O3 catalysts and that the catalysts with 2 wt% CeO2 had the highest catalytic activity among the tested ones at 350 ℃. The XRD and H2-TPR characterizations revealed that the addition of CeO2 decreased the reduction temperature by altering the interaction between Ni and Al2O3, and improved the reducibility of the catalyst. Preliminary stability test of 120 h on stream over the Ni-2CeO2/Al2O3 catalyst at 350 ℃ revealed that the catalyst was much better than the unpromoted one.
基金the National Natural Science Foundation of China(22108115,22478415,and 21978134)Natural Science Foundation of Jiangsu Province(BK20241744)。
文摘Confinement effect is an effective method to enhance carbon dioxide(CO_(2))solubility.In this study,a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([Hmim][NTf_2])/mesoporous titanium dioxide(M-TiO_(2))/water(H_2O)was developed,and its confinement effect was regulated by changing the pore structure of M-TiO_(2).CO_(2) solubility in the hybrid sorbent was measured experimentally,and the thermodynamic properties including Henry's constant and desorption enthalpy were calculated.Furthermore,the confinement effect in the hybrid sorbent was quantified.Additionally,the hybrid sorbent was recycled with a multi-cycle experiment.The results showed that M-TiO_(2) calcined at 773.2 K(MT500)could lead to an efficient confinement effect.CO_(2) solubility in the hybrid sorbent increased by 49.8%compared to that of H_2O when the mass fraction of[Hmim][NTf_2]/MT500 was 5.0%(mass),where the contribution of confinement effect on Gibbs free energy occupied 5.2%.
基金Project supported by the National Key Research and Development Project of China(2022YFC2905202)Natural Science Foundation of Jiangxi Province(20232ACB204014)Youth Jinggang Scholars Program in Jiangxi Province(QNJG2019056)。
文摘The calcium-containing rare earth solution is generated during the recovery processes of NdFeB waste,which is treated as wastewater by enterprises.In this paper,the carbon dioxide carbonization method was applied to the separation of rare earths and calcium in the solution,as well as the preparation of rare earth oxides with a large specific surface.It is shown that the process of CO_(2)carbonization of solution includes reactions such as the dissolution,diffusion and ionization of CO_(2),the carbonate precipitation of rare earth ions,and the neutralization of hydrogen ions.At a pH of 4.5,the carbonization precipitation rate is effectively controlled,enabling homogeneous precipitation and ensuring both high precipitation yield and rare earth oxides purity.In this way,the crystallization of carbonization products is a process dominated by the oriented attachment theory and coexisting with the Ostwald ripening theory,resulting in abundant pores formed by multiple layers of stacking in the products.With the optimal carbonization conditions,the rare earth precipitation yield solution reaches 99.32%.The obtained carbonization products are crystalline(LaCe)(CO_(3))_(3)·8H_(2)O,and the purity of the rare earth oxides is as high as 99.22 wt%.The specific surface area of the rare earth oxides reaches 94.7 m^(2)/g,and its adsorption efficiency for tetracycline hydrochloride in solution can reach 92.6%in a short time.The rare earth oxides are expected to be used as an adsorption material for wastewater treatment and other adsorption environments.
