The geothermal resources in China are primarily found in its sedimentary basins,particularly in the large basins located in eastern China,which hold significant potential for geothermal energy development.The Songliao...The geothermal resources in China are primarily found in its sedimentary basins,particularly in the large basins located in eastern China,which hold significant potential for geothermal energy development.The Songliao,North China,and Zhangzhou basins are of special interest due to their considerable exploration depths,extensive development history,and high levels of research activity.This study focuses on the three basins to analyze their thermal reservoir characteristics in eastern China.Between 2017 and 2023,the research team carried out a comprehensive analysis involving deep boreholes that exceeded 4000 m in depth within these three basins.They meticulously created detailed physical profiles that captured essential characteristics such as porosity,permeability,and thermal properties,reaching down to the basement of each basin.The findings indicated that variations in thermal conductivity within shallow geotechnical layers significantly influence the redistribution of deep thermal energy in the upper layers of the earth.Furthermore,differences in physical properties notably affect heat transport processes.The research proposes distinct heat models tailored for each basin:For the Songliao Basin,a low-permeability model with homogeneous thermal properties is constructed;for the North China Basin,high permeability and thermal conductivity layers are highlighted;and a fracture network controlling water and heat is presented in the Zhangzhou Basin.To elucidate the thermal structure of these basins,the Curie surface and Moho surface were analyzed.The shallow Curie surface indicates ongoing intense thermal activity stemming from crustal heat sources,while a shallow Moho surface signifies historical vigorous mantle thermal activity associated with mantle source heat production.Furthermore,the research evaluates the geothermal resources and the potential for carbon emission reduction in these basins.Total volume of exploitable geothermal fluid is estimated to be 76.9×10^(9) m^(3)/a,corresponding to an annual renewable geothermal energy 1.47×10^(16)k J.The implementation of geothermal energy could lead to a reduction in annual CO_(2)emissions by nearly 2×10^(9) t,which constitutes about 17.4%of China’s national carbon emissions in 2022.This estimation provides invaluable theoretical insights and data support for geothermal exploration and sustainable development in eastern China.展开更多
Intergrowth ferroelectric semiconductors with excellent spontaneous polarization field are highly promising piezo-photocatalytic candidate materials.In addition,developing structural design and revealing polarization ...Intergrowth ferroelectric semiconductors with excellent spontaneous polarization field are highly promising piezo-photocatalytic candidate materials.In addition,developing structural design and revealing polarization enhancement in-depth mechanism are top priorities.Herein,we introduce the intergrowth ferroelectrics Bi_(7)Ti_(4)NbO_(21)thin-layer nanosheets for piezo-photocatalytic CO_(2)reduction.Density functional theory(DFT)calculations indicate that interlayer lattice mismatch leads to increased tilting and rotation angle of Ti/NbO_(6)octahedra on perovskite-like layers,serving as the main reason for increased polarization.Furthermore,the tilting and rotation angle of the interlayer octahedron further increase under stress,suggesting a stronger driving force generated to facilitate charge carrier separation efficiency.Meanwhile,Bi_(7)Ti_(4)NbO_(21)nanosheets provide abundant active sites to effectively adsorb CO_(2)and acquire sensitive stress response,thereby presenting synergistically advanced piezo-photocatalytic CO_(2)reduction activity with a high CO generation rate of 426.97μmol g^(-1)h^(-1).Our work offers new perspectives and directions for initiating and investigating the mechanisms of high-performance intergrowth piezo-photocatalysts.展开更多
Presented herein are the delicate design and synthesis of S-scheme NiTiO_(3)/CdS heterostructures composed of CdS nanoparticles anchored on the surface of NiTiO_(3) nanorods for photocatalytic CO_(2) reduction.Systema...Presented herein are the delicate design and synthesis of S-scheme NiTiO_(3)/CdS heterostructures composed of CdS nanoparticles anchored on the surface of NiTiO_(3) nanorods for photocatalytic CO_(2) reduction.Systematic physicochemical studies demonstrate that NiTiO_(3)/CdS hybrid empowers superior light absorption and enhanced CO_(2) capture and activation.Electron spin resonance validates that the charge carriers in NiTiO_(3)/CdS follow a S-scheme transfer pathway,which powerfully impedes their recombination and promotes their separation.Importantly,the photogenerated holes on CdS are effectively consumed at the hero-interface by the electron from NiTiO_(3),preventing the photo-corrosion of the metal sulfide.As a result,with Co(bpy)_(3)^(2+)as a cocatalyst,NiTiO_(3)/CdS displays a considerable performance for CO_(2) reduction,affording a high CO yield rate of 20.8µmol h^(−1).Moreover,the photocatalyst also manifests substantial stability and good reusability for repeated CO_(2) reaction cycles in the created tandem photochemical system.In addition,the possible CO_(2) photoreduction mechanism is constructed on the basis of the intermediates monitored by in-situ diffuse reflectance infrared Fourier transform spectroscopy.展开更多
As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)poss...As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)possesses favorable electrochemical properties and thermodynamic stability,its intrinsic semiconductor characteristics result in a relatively slow electron transfer rate,limiting the ORR catalytic activity.In this work,the electronic structure of FeWO_(4)is significantly modulated by introducing phosphorus(P)atoms with abundant valence electrons.The P doping can adjust the electronic structure of FeWO_(4)and then optimize oxygen-containing intermediates'absorption/desorption efficiency to achieve improved ORR activity.Furthermore,the sodium chloride template is utilized to construct a porous carbon framework for anchoring phosphorus-doped iron tungstate(P-FeWO_(4)/PNC).The porous carbon skeleton provides numerous active sites for the absorption/desorption and redox reactions on the P-FeWO_(4)/PNC surface and serves as mass transport channels for reactants and intermediates.The P-FeWO_(4)/PNC demonstrates ORR performance(E1/2=0.86 V vs.RHE).Furthermore,the zinc-air batteries incorporating the P-FeWO_(4)/PNC composite demonstrate an increased peak power density(172.2 mW·cm^(-2)),high specific capacity(810.1 mAh·g^(-1)),and sustained long-term cycling stability lasting up to 240 h.This research not only contributes to the advancement of cost-effective tungsten-based non-precious metallic ORR catalysts,but also guides their utilization in zinc-air batteries.展开更多
Electrocatalytic conversion of carbon dioxide(CO_(2))offers an effective method of CO_(2)fixation to mitigate global warming and the energy crisis.However,for supported Ni single-atom catalysts(SACs),which are among t...Electrocatalytic conversion of carbon dioxide(CO_(2))offers an effective method of CO_(2)fixation to mitigate global warming and the energy crisis.However,for supported Ni single-atom catalysts(SACs),which are among the most promising candidates for this application,the relationship between Ni coordination structure and catalytic properties is still under strong debate.Here,we fabricated a series of Ni SACs through precise-engineering of anchor sites on nitrogen-doped carbon(NC)followed by Ni atom anchoring using atomic layer deposition.Among them,a Ni_(1)/NC SAC,with a coordination number(CN)of four but less pyridinic nitrogen(N_(pyri)),achieved over 90%faradaic efϐiciency for CO at potentials from-0.7 to-1.0 V and a mass activity of 6.5 A/mgNi at-0.78 V along with high stability,outperforming other Ni SACs with lower CN and more N_(pyri).Theoretical calculations of various three and four-coordinated Ni_(1)-NxCy structures revealed a linear correlation between the reaction Gibbs free energy for the potential-limiting step and the highest occupied molecular orbital(HOMO)position of Ni-3d orbitals,therein the four-coordinated Ni_(1)-N_(1)C_(3)with the highest HOMO position is identified as the active site for the electrocatalytic CO_(2)-to-CO process,in line with the experimental results.展开更多
Regulating the electronic structure and oxygencontaining intermediates adsorption behavior on Fe-based catalysts is of great significance to cope with the sluggish oxygen reduction reaction(ORR)kinetics,but it still r...Regulating the electronic structure and oxygencontaining intermediates adsorption behavior on Fe-based catalysts is of great significance to cope with the sluggish oxygen reduction reaction(ORR)kinetics,but it still remains a great challenge.In this work,Fe atom clusters(Fe_(AC))modified by high-density Cu single atoms(Cu_(SA))in a N,S-doped porous carbon substrate(Fe_(AC)/Cu_(SA)@NCS)is reported for enhanced ORR electrocatalysis.Fe_(AC)/Cu_(SA)@NCS exhibits excellent ORR performance with a half-wave potential(E_(1/2))of 0.911 V,a high four-electron process selectivity and excellent stability.The ORR performance is also verified in the Fe_(AC)/Cu_(SA)@NCS-based Zn-air battery,which shows a high peak power density of 192.67 mW cm^(-2),a higher specific capacity of 808.3 mAh g^(-1)and impressive charge-discharge cycle stability.Moreover,density functional theory calculations show that Cu single atoms synergistically modulate the electronic structure Fe active atoms in Fe atomic clusters,reducing the energy barrier of the rate-determining step(i.e.,*OH desorption)on Fe_(AC)/Cu_(SA)@NCS.This work provides an effective way to regulate the electronic structure of Fe-based catalysts and optimize their electrocatalytic activity based on the introduction of a second metal source.展开更多
Proton exchange membrane fuel cells have been identified as a potentially valuable technology for the efficient conversion of hydrogen energy into electrical energy.Nevertheless,one significant constraint on the perfo...Proton exchange membrane fuel cells have been identified as a potentially valuable technology for the efficient conversion of hydrogen energy into electrical energy.Nevertheless,one significant constraint on the performance of fuel cells is the oxygen reduction reaction(ORR).It is meaningful to progress the development of representative ORR electrocatalysts.In recent times,there has been an intensified focus on single-atom catalysts(SACs)due to the advantages of homogeneous distribution and high atom utilization efficiency.In particular,the coordination structure of metal sites plays an important role in the electrochemical performance of SACs.However,the relationship between coordination structures and catalytic performance remains unclear.In this review,we summarized the research progress on SACs in electrocatalytic ORR in recent years.Then the structure-activity relationship in the symmetric and asymmetric coordination structures of SACs was clarified.We further proposed rational design principles for regulating the coordination structure of SACs.Finally,the opportunities and challenges were discussed.展开更多
The underappreciated role of supports has severely constrained the modification of single-atom catalysts.It's important to develop a strategy for achieving a strong synergy between catalytic structures and active ...The underappreciated role of supports has severely constrained the modification of single-atom catalysts.It's important to develop a strategy for achieving a strong synergy between catalytic structures and active sites.Here,we devise a structure-inducing method involving the manipulation of the chemical reaction environment and spin-state of Cu single-atom with helical carbon nanotube(HCNT)for CO_(2)efficient electroreduction to formate.Utilizing in situ characterization and finite element simulation,we find that the helical structure effectively enriches HCO_(3)-and OH-on the surface of Cu-N_(2)O_(2)/HCNT catalyst during electrocatalytic CO_(2)reduction,creating a favorable interfacial environment for formate generation.Magnetic characterizations and theoretical calculations reveal spin polarization of Cu-N_(2)O_(2)sites,yielding readily polarized magnetic moments.Consequently,a spin-ordered phase emerges on the surface of Cu-N_(2)O_(2)/HCNT under a magnetic field,enhancing formate selectivity.Impressively,Cu-N_(2)O_(2)/HCNT achieves93.6%formate selectivity at-0.80 V vs.RHE under 200 mT.Under an in situ magnetic field,it maintains over 80%formate selectivity at-175 mA/cm^(2)for 100 h.Our findings offer novel insights into single-atom catalyst modification.展开更多
Proton exchange membrane fuel cells(PEMFCs)constitute a promising avenue for environmentally friendly power generation.However,the reliance on unsustainable platinum-based electrocatalysts used at the electrodes poses...Proton exchange membrane fuel cells(PEMFCs)constitute a promising avenue for environmentally friendly power generation.However,the reliance on unsustainable platinum-based electrocatalysts used at the electrodes poses challenges to the commercial viability of PEMFCs.Non-platinum group metal(non-PGM)alternatives,like nitrogen-coordinated transition metals in atomic dispersion(M–N–C catalysts),show significant potential.This work presents a comparative study of two distinct sets of Fe–N–C materials,prepared by pyrolyzing hybrid composites of polyaniline(PANI)and iron(Ⅱ)chloride on a hard template.One set uses bipyridine(BPy)as an additional nitrogen source and iron ligand,offering an innovative approach.The findings reveal that the choice of pyrolysis temperature and atmosphere influences the catalyst properties.The use of ammonia in pyrolysis emerges as a crucial parameter for promoting atomic dispersion of iron,as well as increasing surface area and porosity.The optimal catalyst,prepared using BPy and ammonia,exhibits a half-wave potential of 0.834 V in 0.5 M H_(2)SO_(4)(catalyst loading of 0.6 mg cm^(-2)),a mass activity exceeding 3 A g^(-1)and high stability in acidic electrolyte,positioning it as a promising non-PGM structure in the field.展开更多
This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the correspo...This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the corresponding ester[Fe_(2)(CO)_(6)(μ‑tedt)](2),where tedt=SCH_(2)CH(CH_(2)OOC(5‑C_(3)HNSCH_(3)))S.Further reactions of complex 2 with tri(ptolyl)phosphine(tp)or tris(4‑fluorophenyl)phosphine(fp)gave the phosphine‑substituted derivatives[Fe_(2)(CO)_(5)(tp)(μ‑tedt)](3)and[Fe_(2)(CO)_(5)(fp)(μ‑tedt)](4).The structures of the newly prepared complexes were elucidated by elemental analysis,NMR,IR,and X‑ray photoelectron spectroscopy.Moreover,single‑crystal X‑ray diffraction analysis confirmed their molecular structures,showing that they contain a di‑iron core ligated by a bridged dithiolate bearing a thiazole moiety and terminal carbonyls.The electrochemical and electrocatalytic proton reduction were probed by cyclic voltammetry,revealing that three complexes can catalyze the reduction of protons to H_(2) under the electrochemical conditions.For comparison,complex 4 possessed the best efficiency with a turnover frequency of 23.5 s^(-1)at 10 mmol·L^(-1)HOAc concentration.In addition,the fungicidal activity of these complexes was also investigated in this study.CCDC:2477511,2;2477512,3;2477513,4.展开更多
Countries around the world have been making efforts to reduce pollutant emissions. However, the response of global black carbon(BC) aging to emission changes remains unclear. Using the Community Atmosphere Model versi...Countries around the world have been making efforts to reduce pollutant emissions. However, the response of global black carbon(BC) aging to emission changes remains unclear. Using the Community Atmosphere Model version 6 with a machine-learning-integrated four-mode version of the Modal Aerosol Module, we quantify global BC aging responses to emission reductions for 2011–2018 and for 2050 and 2100 under carbon neutrality. During 2011–18, global trends in BC aging degree(mass ratio of coatings to BC, R_(BC)) exhibited marked regional disparities, with a significant increase in China(5.4% yr^(-1)), which contrasts with minimal changes in the USA, Europe, and India. The divergence is attributed to opposing trends in secondary organic aerosol(SOA) and sulfate coatings, driven by regional changes in the emission ratios of corresponding coating precursors to BC(volatile organic compounds-VOCs/BC and SO_(2)/BC). Projections under carbon neutrality reveal that R_(BC) will increase globally by 47%(118%) in 2050(2100), with strong convergent increases expected across major source regions. The R_(BC) increase, primarily driven by enhanced SOA coatings due to sharper BC reductions relative to VOCs, will enhance the global BC mass absorption cross-section(MAC) by 11%(17%) in 2050(2100).Consequently, although the global BC burden will decline sharply by 60%(76%), the enhanced MAC partially offsets the magnitude of the decline in the BC direct radiative effect, resulting in the moderation of global BC DRE decreases to 88%(92%) of the BC burden reductions in 2050(2100). This study highlights the globally enhanced BC aging and light absorption capacity under carbon neutrality, thereby partly offsetting the impact of BC direct emission reductions on future changes in BC radiative effects globally.展开更多
In order to explore the reduction pathways of zinc oxide in LiCl molten salt and the optimal process,experiments were conducted in an alumina crucible using metallic lithium as the reducing agent and lithium chloride ...In order to explore the reduction pathways of zinc oxide in LiCl molten salt and the optimal process,experiments were conducted in an alumina crucible using metallic lithium as the reducing agent and lithium chloride molten salt as the reaction medium at 923 K.The study assessed the effects of lithium thermochemical reduction and electrolytic reduction of ZnO.The volatilization behavior of metal oxides in molten salts,the equivalent of a reducing agent,reduction time,amount of molten salt,stirring time,and the method of reduction feed were investigated for their impacts on the reduction yield and product composition.X-ray powder diffraction(XRD)analysis of the products showed that lithium reduction of ZnO not only produced metallic Zn but also formed a LiZn alloy.Electrolytic reduction can be used to obtain the metallic Zn product by controlling the potential below-2.2 V(vs Ag/Ag^(+)).Moreover,sintered oxides and higher electrode potentials could enhance the efficiency of electrolysis.Under the optimal reaction conditions determined experimentally,the lithium reduction experiment achieved a yield of 77.2%after a 12-h test,and the electrolytic reduction reached a yield of 85.4%after a 6-h test.展开更多
The electrochemical conversion of toxic nitrite(NO_(2)-)is a promising approach for the simultaneous removal of nitrogen contaminants and synthesis of ammonia(NH_(3)).In this study,we present the Er-doping-induced ele...The electrochemical conversion of toxic nitrite(NO_(2)-)is a promising approach for the simultaneous removal of nitrogen contaminants and synthesis of ammonia(NH_(3)).In this study,we present the Er-doping-induced electronic modulation of CoP integrated with nitrogen-doped carbon(CN)nanosheets supported on a titanium mesh(Er-CoP@NC/TM)for the electrocatalytic NO_(2)-reduction reaction(eNO_(2)-RR)for NH_(3)synthesis.The catalyst demonstrates a high Faraday efficiency of 97.08±2.22%and a high yield of 2087.60±17.10μmol h^(-1)cm^(-2)for NH_(3)production.Characterization and theoretical calculations revealed that Er-doping facilitated the electronic modulation of CoP in Er-CoP@NC/TM,which regulated the adsorption behaviors of intermediates and was the rate-limiting step for the eNO_(2)-RR,thereby enhancing the electrocatalytic performance.Quenching experiments and electron paramagnetic resonance tests suggest that both direct electrocatalytic reduction by active hydrogen and electron transfer are critical for the eNO_(2)-RR for NH_(3)synthesis.Furthermore,Er-CoP@NC/TM exhibited high performance across a wide range of NO_(2)-concentrations(0.05-0.1 mol L^(-1))and pH values(4-13).In addition,the catalyst demonstrated strong resistance to anions and a long cycle life in simulated wastewater environments.This study offers a powerful approach for the remediation of NO_(2)-wastewater and recovery of valuable inorganic compounds.展开更多
Perovskite oxides have shown great potential application in fuel cells due to the unique crystal structures and tunable composition as well as effective capability toward the oxygen reduction reaction(ORR),whereas the...Perovskite oxides have shown great potential application in fuel cells due to the unique crystal structures and tunable composition as well as effective capability toward the oxygen reduction reaction(ORR),whereas the investigation on the electrocatalytic performance of perovskite oxides toward the two-electron ORR to H_(2)O_(2)production remains very limited.Herein,a facile synthetic method has been developed to prepare La_(2)Sn_(2)O_(7)@La-doped ZnSnO_(3)heterostructures comprising of amorphous La_(2)Sn_(2)O_(7)and crystalline La-doped ZnSnO_(3).The optimal La_(2)Sn_(2)O_(7)@Ladoped ZnSnO_(3)heterostructures catalyst exhibits a significantly improved two-electron ORR performance to H_(2)O_(2)production with onset potential of 0.77 V and large current density of 2.51 m A.cm^(-2)at 0.1 V compared to ZnSnO_(3)(0.75 V,1.80 m A.cm^(-2),0.11 m A) as well as maintains high H_(2)O_(2)selectivity of 80%,which has been theoretically demonstrated to be contributed to the synergistic effect of amorphous La_(2)Sn_(2)O_(7)and crystalline La-doped ZnSnO_(3).Moreover,high H_(2)O_(2)yield rate of 2.9 m M.h^(-1)at 0.1 V can be achieved with a superior turnover frequency(TOF) of3.31 × 10^(-2)s^(-1)compared to the ZnSnO_(3)catalyst(2.10 × 10^(-2)s^(-1)).This work reveals the great potential of perovskite oxide as promising candidates for the environmentally friendly synthesis of hydrogen peroxide.展开更多
Catalytic reduction of nitrate over bimetallic catalysts has emerged as a technology for sustainable treatment of nitrate-containing groundwater.However,the structure of bimetallic has been much less investigated for ...Catalytic reduction of nitrate over bimetallic catalysts has emerged as a technology for sustainable treatment of nitrate-containing groundwater.However,the structure of bimetallic has been much less investigated for catalyst optimization.Herein,two main types of Pd-Cu bimetallic nanocrystal structures,heterostructure and intermetallic,were prepared and characterized using high-resolution transmission electron microscopy(HRTEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The results show that two individual Pd and Cu nanocrystals with a mixed interface exist in the heterostructure nanocrystals,while Pd and Cu atoms are uniformly distributed across the intermetallic Pd-Cu nanocrystals.The catalytic nitrate reduction experiments were carried out in a semibatch reactor under constant hydrogen flow.The nitrate conversion rate of the heterostructure Pd-Cu nanocrystals supported onα-Al_(2)O_(3),γ-Al_(2)O_(3),SBA-15,and XC-72R exhibited 3.82-,6.76-,4.28-,2.44-fold enhancements relative to the intermetallic nanocrystals,and the nitrogen and nitrite were the main products for the heterostructure and intermetallic Pd-Cu nanocrystals,respectively.This indicates that the catalytic nitrate reduction over Pd-Cu catalyst is sensitive to the bimetallic structures of the catalysts,and heterostructure bimetallic nanocrystals exhibit better catalytic performances on both the activity and selectivity,which may provide new insights into the design and optimization of catalysts to improve catalytic activity and selectivity for nitrate reduction in water.展开更多
Electrochemical nitrate reduction(NO_(3)RR)offers a promising avenue for treating nitrate-contaminated water and recovering ammonia(NH_(3)),yet the complexities of direct electron transfer(DET)and hydrogen atom transf...Electrochemical nitrate reduction(NO_(3)RR)offers a promising avenue for treating nitrate-contaminated water and recovering ammonia(NH_(3)),yet the complexities of direct electron transfer(DET)and hydrogen atom transfer(HAT)mechanisms crucial for efficiency remain elusive.This study bridges the gap with a combined experimental and theoretical approach,elucidating the impact of catalyst structure on NO3RR pathways.We discover that catalysts favoring strong NO_(3^(-))adsorption and efficient water dissociation were more inclined towards DET,enhancing denitrification.The Fe@Fe_(3)O_(4)/FF cathode,leveraging the synergistic interplay between metallic Fe and Fe_(3)O_(4),excelled in NO3RR via DET,achieving an NH3yield of 0.28 mmol h-1cm-2and a Faradaic efficiency of 95.7%for NH3at-1.6 V(vs.SCE),with minimal nitrite accumulation at 100 mmol/L nitrate.Conversely,the Fe/FF and Fe_(3)O_(4)/CC cathodes showed reduced NH3production and increased nitrite levels,attributed to the lack of Fe_(3)O_(4)and metallic Fe,respectively,resulting in a dominant HAT mechanism.Moreover,Fe@Fe_(3)O_(4)/FF facilitated complete denitrification in real wastewater treatment by harnessing Cl^(-)for electrochemically mediated breakpoint chlorination.This research not only deepens our understanding of NO3RR mechanisms but also paves the way for designing superior nitrate reduction catalysts.展开更多
The photocatalytic reduction of CO_(2)presents a promising avenue for carbon fuel conversion.However,the efficiency of charge utilization remains a critical barrier to industrial applications.In this study,we introduc...The photocatalytic reduction of CO_(2)presents a promising avenue for carbon fuel conversion.However,the efficiency of charge utilization remains a critical barrier to industrial applications.In this study,we introduce a tandem design of Bi_(2)WO_(6)-BiOCl with an atomically matched interface,achieving highly efficient photoreduction of CO_(2)to CO.By incorporating WO_(4)^(2-)ions and tuning coordination environment,the(110)facet of BiOCl was in-situ grown on the(200)facet of Bi_(2)WO_(6).Compared to single phases and ball-milling samples,Bi_(2)WO_(6)-BiOCl exhibits a remarkable CO yield of 68.03μmol g^(-1)h^(-1)with a selectivity of 98%.Atomic visualization and coordination analysis confirm the formation of a coherent interface that facilitates charge migration for efficient electron transport.Density functional theory(DFT)calculations and in-situ Fourier transform infrared(FTIR)spectroscopy provide insights into the intrinsic active sites and reaction mechanisms.The proposed lattice engineering strategies offer a new paradigm for the rational design of heterostructures beyond traditional band alignment at the atomic scale.展开更多
Inspired by the aquatic-adapted pit structures of the Cybister beetles that enable high-speed swimming,this study employs warp-knitted technology to fabricate drag-reduction swimwear textiles.Eight distinct fabric mor...Inspired by the aquatic-adapted pit structures of the Cybister beetles that enable high-speed swimming,this study employs warp-knitted technology to fabricate drag-reduction swimwear textiles.Eight distinct fabric morphologies were produced,and a self-developed high-precision dynamic drag measurement device was used to systematically analyze the mechanisms underlying the drag-reduction performance of these biomimetic pit structures.The device incorporates a servomotor,ball screw linkage,and high-precision tension sensor,enabling real-time and accurate detection of fluid drag forces.It effectively overcomes the limitations of traditional indirect measurement methods,including dynamic response lag and insufficient accuracy.Experimental results demonstrate that the hydrophobic small-pit fabric(4^(#))achieves an 84% drag reduction at 400 mm/s,outperforming the control sample(warp-knitted fabric 7^(#)).This significant reduction is attributed to the Cassie state established on the hydrophobic surface,which substantially decreases viscous drag and the microvortices generated by the pit structures,which delay flow separation and effectively minimize pressure drag.Furthermore,small-pit fabrics demonstrate a drag reduction rate 26% to 50% higher than that of large-pit structures,highlighting the critical importance of matching the pit scale to the thickness of the near-wall viscous sublayer for optimal drag reduction.This study establishes a theoretical foundation for the biomimetic design of high-performance drag-reduction swimsuits.The developed drag-measuring device also provides a standardized experimental platform for hydrodynamic studies of flexible materials,supporting a shift from empirical design methodologies to theory-driven approaches in drag-reduction technology and exhibiting significant potential for future advancements.展开更多
Due to its high space utilization efficiency and overall advantages,the"integrated station-bridge"design is widely used in high-speed rail stations.However,compared to traditional separated station-bridge st...Due to its high space utilization efficiency and overall advantages,the"integrated station-bridge"design is widely used in high-speed rail stations.However,compared to traditional separated station-bridge structures,the structure-borne noise generated by high-speed trains passing through these stations is more pronounced.To investigate the structure-borne noise radiation characteristics of these station designs,we developed a noise simulation model for the"integrated station-bridge"high-speed railway station and validated its reliability through comparison with test results.Building on this,we implemented the floating track slab between the track structure and the station platform to mitigate structure-borne noise.Furthermore,we examined the factors influencing the noise reduction effectiveness of the floating floor.The results indicated that train passages result in significant structure-borne noise issues in"integrated station-bridge"stations.The maximum sound pressure levels at the waiting hall and platform exceed 70 dB(A).After the implementation of the floating floor,the maximum sound pressure levels on each floor decreased by 11–14 dB(A).Additionally,increasing the thickness of the floating floor and reducing the stiffness of the steel spring bearings both enhanced the noise reduction effectiveness of the floating floor.展开更多
SnS has emerged as an attractive catalyst for the electrochemical CO_(2)reduction reaction(CO_(2)RR)to formate,while its long-term operational stability is hindered by the self-reduction of Sn^(2+) and sulfur dissolut...SnS has emerged as an attractive catalyst for the electrochemical CO_(2)reduction reaction(CO_(2)RR)to formate,while its long-term operational stability is hindered by the self-reduction of Sn^(2+) and sulfur dissolution.Thus,maintaining high current efficiency across a wide negative potential range to achieve high production rates of formate remains a significant challenge.In this study,we present a heterostructure constructed with SnS and CuS for efficient CO_(2)RR to formate.The SnS-CuS(30)exhibits a remarkable formate Faradaic efficiency(FE_(f))of 93.94%at−1 V vs.reversible hydrogen electrode(RHE)and demonstrates long-term stability for 7.5 h,maintaining high activity(with an average FE_(f)of 85.6%)across a wide negative potential range(from-0.8 to-1.2 V(vs.RHE)).The results reveal that the heterogeneous interface between SnS and CuS mitigates the self-reduction issue of SnS by sacrificing Cu^(2+),highlighting that the true active species is SnS,which effectively resists structural changes during the electrolysis process under the protection of CuS.The synergistic interaction within the CuS and SnS heterostructure,combined with the tendency for electron self-conduction,enables the catalyst to maintain high formate activity and selectivity across a wide potential range.Furthermore,theoretical results further indicate that the incorporation of CuS enhances CO_(2)adsorption and lowers the energy barrier for the formation of formate intermediates.This study inspires the concept of applying protective layers to active species,promoting high selectivity in Sn-based electrocatalysts.展开更多
基金funded by the Basic Scientific Research of China Geological Academy(YK202305)National Key R&D Program of China(2019YFB1504101)+1 种基金National Natural Science Foundation of China(41602271)China Geological Survey(DD20160207 and DD20189112)。
文摘The geothermal resources in China are primarily found in its sedimentary basins,particularly in the large basins located in eastern China,which hold significant potential for geothermal energy development.The Songliao,North China,and Zhangzhou basins are of special interest due to their considerable exploration depths,extensive development history,and high levels of research activity.This study focuses on the three basins to analyze their thermal reservoir characteristics in eastern China.Between 2017 and 2023,the research team carried out a comprehensive analysis involving deep boreholes that exceeded 4000 m in depth within these three basins.They meticulously created detailed physical profiles that captured essential characteristics such as porosity,permeability,and thermal properties,reaching down to the basement of each basin.The findings indicated that variations in thermal conductivity within shallow geotechnical layers significantly influence the redistribution of deep thermal energy in the upper layers of the earth.Furthermore,differences in physical properties notably affect heat transport processes.The research proposes distinct heat models tailored for each basin:For the Songliao Basin,a low-permeability model with homogeneous thermal properties is constructed;for the North China Basin,high permeability and thermal conductivity layers are highlighted;and a fracture network controlling water and heat is presented in the Zhangzhou Basin.To elucidate the thermal structure of these basins,the Curie surface and Moho surface were analyzed.The shallow Curie surface indicates ongoing intense thermal activity stemming from crustal heat sources,while a shallow Moho surface signifies historical vigorous mantle thermal activity associated with mantle source heat production.Furthermore,the research evaluates the geothermal resources and the potential for carbon emission reduction in these basins.Total volume of exploitable geothermal fluid is estimated to be 76.9×10^(9) m^(3)/a,corresponding to an annual renewable geothermal energy 1.47×10^(16)k J.The implementation of geothermal energy could lead to a reduction in annual CO_(2)emissions by nearly 2×10^(9) t,which constitutes about 17.4%of China’s national carbon emissions in 2022.This estimation provides invaluable theoretical insights and data support for geothermal exploration and sustainable development in eastern China.
基金support from the Natural Science Foundation of Jiangsu Province(BK20220596)Innovative science and technology platform project of cooperation between Yangzhou City and Yangzhou University,China(No.YZ202026305)+1 种基金Natural Science Foundation of China(21922202,21673202 and 22272147)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Intergrowth ferroelectric semiconductors with excellent spontaneous polarization field are highly promising piezo-photocatalytic candidate materials.In addition,developing structural design and revealing polarization enhancement in-depth mechanism are top priorities.Herein,we introduce the intergrowth ferroelectrics Bi_(7)Ti_(4)NbO_(21)thin-layer nanosheets for piezo-photocatalytic CO_(2)reduction.Density functional theory(DFT)calculations indicate that interlayer lattice mismatch leads to increased tilting and rotation angle of Ti/NbO_(6)octahedra on perovskite-like layers,serving as the main reason for increased polarization.Furthermore,the tilting and rotation angle of the interlayer octahedron further increase under stress,suggesting a stronger driving force generated to facilitate charge carrier separation efficiency.Meanwhile,Bi_(7)Ti_(4)NbO_(21)nanosheets provide abundant active sites to effectively adsorb CO_(2)and acquire sensitive stress response,thereby presenting synergistically advanced piezo-photocatalytic CO_(2)reduction activity with a high CO generation rate of 426.97μmol g^(-1)h^(-1).Our work offers new perspectives and directions for initiating and investigating the mechanisms of high-performance intergrowth piezo-photocatalysts.
基金financially supported by the National Natural Science Foundation of China(Nos.22372035,22302039,22311540011,and 21973014)the“111 Project”(No.D16008).
文摘Presented herein are the delicate design and synthesis of S-scheme NiTiO_(3)/CdS heterostructures composed of CdS nanoparticles anchored on the surface of NiTiO_(3) nanorods for photocatalytic CO_(2) reduction.Systematic physicochemical studies demonstrate that NiTiO_(3)/CdS hybrid empowers superior light absorption and enhanced CO_(2) capture and activation.Electron spin resonance validates that the charge carriers in NiTiO_(3)/CdS follow a S-scheme transfer pathway,which powerfully impedes their recombination and promotes their separation.Importantly,the photogenerated holes on CdS are effectively consumed at the hero-interface by the electron from NiTiO_(3),preventing the photo-corrosion of the metal sulfide.As a result,with Co(bpy)_(3)^(2+)as a cocatalyst,NiTiO_(3)/CdS displays a considerable performance for CO_(2) reduction,affording a high CO yield rate of 20.8µmol h^(−1).Moreover,the photocatalyst also manifests substantial stability and good reusability for repeated CO_(2) reaction cycles in the created tandem photochemical system.In addition,the possible CO_(2) photoreduction mechanism is constructed on the basis of the intermediates monitored by in-situ diffuse reflectance infrared Fourier transform spectroscopy.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.22178148 and 22278193)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)possesses favorable electrochemical properties and thermodynamic stability,its intrinsic semiconductor characteristics result in a relatively slow electron transfer rate,limiting the ORR catalytic activity.In this work,the electronic structure of FeWO_(4)is significantly modulated by introducing phosphorus(P)atoms with abundant valence electrons.The P doping can adjust the electronic structure of FeWO_(4)and then optimize oxygen-containing intermediates'absorption/desorption efficiency to achieve improved ORR activity.Furthermore,the sodium chloride template is utilized to construct a porous carbon framework for anchoring phosphorus-doped iron tungstate(P-FeWO_(4)/PNC).The porous carbon skeleton provides numerous active sites for the absorption/desorption and redox reactions on the P-FeWO_(4)/PNC surface and serves as mass transport channels for reactants and intermediates.The P-FeWO_(4)/PNC demonstrates ORR performance(E1/2=0.86 V vs.RHE).Furthermore,the zinc-air batteries incorporating the P-FeWO_(4)/PNC composite demonstrate an increased peak power density(172.2 mW·cm^(-2)),high specific capacity(810.1 mAh·g^(-1)),and sustained long-term cycling stability lasting up to 240 h.This research not only contributes to the advancement of cost-effective tungsten-based non-precious metallic ORR catalysts,but also guides their utilization in zinc-air batteries.
文摘Electrocatalytic conversion of carbon dioxide(CO_(2))offers an effective method of CO_(2)fixation to mitigate global warming and the energy crisis.However,for supported Ni single-atom catalysts(SACs),which are among the most promising candidates for this application,the relationship between Ni coordination structure and catalytic properties is still under strong debate.Here,we fabricated a series of Ni SACs through precise-engineering of anchor sites on nitrogen-doped carbon(NC)followed by Ni atom anchoring using atomic layer deposition.Among them,a Ni_(1)/NC SAC,with a coordination number(CN)of four but less pyridinic nitrogen(N_(pyri)),achieved over 90%faradaic efϐiciency for CO at potentials from-0.7 to-1.0 V and a mass activity of 6.5 A/mgNi at-0.78 V along with high stability,outperforming other Ni SACs with lower CN and more N_(pyri).Theoretical calculations of various three and four-coordinated Ni_(1)-NxCy structures revealed a linear correlation between the reaction Gibbs free energy for the potential-limiting step and the highest occupied molecular orbital(HOMO)position of Ni-3d orbitals,therein the four-coordinated Ni_(1)-N_(1)C_(3)with the highest HOMO position is identified as the active site for the electrocatalytic CO_(2)-to-CO process,in line with the experimental results.
基金financially supported by the National Natural Science Foundation of China(No.22278042)the National Natural Science Foundation of Jiangsu Province(No.BK20240567)+2 种基金the Introduction and Cultivation of Leading Innovative Talents Foundation of Changzhou,Jiangsu Province(No.CQ20220093)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.24KJD530001)the Open Project Program of Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science(No.M2024-7),MOE
文摘Regulating the electronic structure and oxygencontaining intermediates adsorption behavior on Fe-based catalysts is of great significance to cope with the sluggish oxygen reduction reaction(ORR)kinetics,but it still remains a great challenge.In this work,Fe atom clusters(Fe_(AC))modified by high-density Cu single atoms(Cu_(SA))in a N,S-doped porous carbon substrate(Fe_(AC)/Cu_(SA)@NCS)is reported for enhanced ORR electrocatalysis.Fe_(AC)/Cu_(SA)@NCS exhibits excellent ORR performance with a half-wave potential(E_(1/2))of 0.911 V,a high four-electron process selectivity and excellent stability.The ORR performance is also verified in the Fe_(AC)/Cu_(SA)@NCS-based Zn-air battery,which shows a high peak power density of 192.67 mW cm^(-2),a higher specific capacity of 808.3 mAh g^(-1)and impressive charge-discharge cycle stability.Moreover,density functional theory calculations show that Cu single atoms synergistically modulate the electronic structure Fe active atoms in Fe atomic clusters,reducing the energy barrier of the rate-determining step(i.e.,*OH desorption)on Fe_(AC)/Cu_(SA)@NCS.This work provides an effective way to regulate the electronic structure of Fe-based catalysts and optimize their electrocatalytic activity based on the introduction of a second metal source.
基金supported the National Natural Science Foundation of China(Nos.22108306 and 22478432)Taishan Scholars Program of Shandong Province(No.tsqn201909065)the Natural Science Foundation of Shandong Province(Nos.ZR2024JQ004 and ZR2021YQ15).
文摘Proton exchange membrane fuel cells have been identified as a potentially valuable technology for the efficient conversion of hydrogen energy into electrical energy.Nevertheless,one significant constraint on the performance of fuel cells is the oxygen reduction reaction(ORR).It is meaningful to progress the development of representative ORR electrocatalysts.In recent times,there has been an intensified focus on single-atom catalysts(SACs)due to the advantages of homogeneous distribution and high atom utilization efficiency.In particular,the coordination structure of metal sites plays an important role in the electrochemical performance of SACs.However,the relationship between coordination structures and catalytic performance remains unclear.In this review,we summarized the research progress on SACs in electrocatalytic ORR in recent years.Then the structure-activity relationship in the symmetric and asymmetric coordination structures of SACs was clarified.We further proposed rational design principles for regulating the coordination structure of SACs.Finally,the opportunities and challenges were discussed.
基金the support and funding from the Fundamental Research Funds for Central Universitiessupported by the Shanghai Science and Technology Commission(19DZ2271500)supported by Beijing Zhongkebaice Technology Service Co.,Ltd.
文摘The underappreciated role of supports has severely constrained the modification of single-atom catalysts.It's important to develop a strategy for achieving a strong synergy between catalytic structures and active sites.Here,we devise a structure-inducing method involving the manipulation of the chemical reaction environment and spin-state of Cu single-atom with helical carbon nanotube(HCNT)for CO_(2)efficient electroreduction to formate.Utilizing in situ characterization and finite element simulation,we find that the helical structure effectively enriches HCO_(3)-and OH-on the surface of Cu-N_(2)O_(2)/HCNT catalyst during electrocatalytic CO_(2)reduction,creating a favorable interfacial environment for formate generation.Magnetic characterizations and theoretical calculations reveal spin polarization of Cu-N_(2)O_(2)sites,yielding readily polarized magnetic moments.Consequently,a spin-ordered phase emerges on the surface of Cu-N_(2)O_(2)/HCNT under a magnetic field,enhancing formate selectivity.Impressively,Cu-N_(2)O_(2)/HCNT achieves93.6%formate selectivity at-0.80 V vs.RHE under 200 mT.Under an in situ magnetic field,it maintains over 80%formate selectivity at-175 mA/cm^(2)for 100 h.Our findings offer novel insights into single-atom catalyst modification.
基金funding from the Hellenic Foundation for Research and Innovation(HFRI)under grant agreement No 3655.
文摘Proton exchange membrane fuel cells(PEMFCs)constitute a promising avenue for environmentally friendly power generation.However,the reliance on unsustainable platinum-based electrocatalysts used at the electrodes poses challenges to the commercial viability of PEMFCs.Non-platinum group metal(non-PGM)alternatives,like nitrogen-coordinated transition metals in atomic dispersion(M–N–C catalysts),show significant potential.This work presents a comparative study of two distinct sets of Fe–N–C materials,prepared by pyrolyzing hybrid composites of polyaniline(PANI)and iron(Ⅱ)chloride on a hard template.One set uses bipyridine(BPy)as an additional nitrogen source and iron ligand,offering an innovative approach.The findings reveal that the choice of pyrolysis temperature and atmosphere influences the catalyst properties.The use of ammonia in pyrolysis emerges as a crucial parameter for promoting atomic dispersion of iron,as well as increasing surface area and porosity.The optimal catalyst,prepared using BPy and ammonia,exhibits a half-wave potential of 0.834 V in 0.5 M H_(2)SO_(4)(catalyst loading of 0.6 mg cm^(-2)),a mass activity exceeding 3 A g^(-1)and high stability in acidic electrolyte,positioning it as a promising non-PGM structure in the field.
文摘This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the corresponding ester[Fe_(2)(CO)_(6)(μ‑tedt)](2),where tedt=SCH_(2)CH(CH_(2)OOC(5‑C_(3)HNSCH_(3)))S.Further reactions of complex 2 with tri(ptolyl)phosphine(tp)or tris(4‑fluorophenyl)phosphine(fp)gave the phosphine‑substituted derivatives[Fe_(2)(CO)_(5)(tp)(μ‑tedt)](3)and[Fe_(2)(CO)_(5)(fp)(μ‑tedt)](4).The structures of the newly prepared complexes were elucidated by elemental analysis,NMR,IR,and X‑ray photoelectron spectroscopy.Moreover,single‑crystal X‑ray diffraction analysis confirmed their molecular structures,showing that they contain a di‑iron core ligated by a bridged dithiolate bearing a thiazole moiety and terminal carbonyls.The electrochemical and electrocatalytic proton reduction were probed by cyclic voltammetry,revealing that three complexes can catalyze the reduction of protons to H_(2) under the electrochemical conditions.For comparison,complex 4 possessed the best efficiency with a turnover frequency of 23.5 s^(-1)at 10 mmol·L^(-1)HOAc concentration.In addition,the fungicidal activity of these complexes was also investigated in this study.CCDC:2477511,2;2477512,3;2477513,4.
基金supported by the National Natural Science Foundation of China (42505149,41925023,U2342223,42105069,and 91744208)the China Postdoctoral Science Foundation (2025M770303)+1 种基金the Fundamental Research Funds for the Central Universities (14380230)the Jiangsu Funding Program for Excellent Postdoctoral Talent,and Jiangsu Collaborative Innovation Center of Climate Change。
文摘Countries around the world have been making efforts to reduce pollutant emissions. However, the response of global black carbon(BC) aging to emission changes remains unclear. Using the Community Atmosphere Model version 6 with a machine-learning-integrated four-mode version of the Modal Aerosol Module, we quantify global BC aging responses to emission reductions for 2011–2018 and for 2050 and 2100 under carbon neutrality. During 2011–18, global trends in BC aging degree(mass ratio of coatings to BC, R_(BC)) exhibited marked regional disparities, with a significant increase in China(5.4% yr^(-1)), which contrasts with minimal changes in the USA, Europe, and India. The divergence is attributed to opposing trends in secondary organic aerosol(SOA) and sulfate coatings, driven by regional changes in the emission ratios of corresponding coating precursors to BC(volatile organic compounds-VOCs/BC and SO_(2)/BC). Projections under carbon neutrality reveal that R_(BC) will increase globally by 47%(118%) in 2050(2100), with strong convergent increases expected across major source regions. The R_(BC) increase, primarily driven by enhanced SOA coatings due to sharper BC reductions relative to VOCs, will enhance the global BC mass absorption cross-section(MAC) by 11%(17%) in 2050(2100).Consequently, although the global BC burden will decline sharply by 60%(76%), the enhanced MAC partially offsets the magnitude of the decline in the BC direct radiative effect, resulting in the moderation of global BC DRE decreases to 88%(92%) of the BC burden reductions in 2050(2100). This study highlights the globally enhanced BC aging and light absorption capacity under carbon neutrality, thereby partly offsetting the impact of BC direct emission reductions on future changes in BC radiative effects globally.
文摘In order to explore the reduction pathways of zinc oxide in LiCl molten salt and the optimal process,experiments were conducted in an alumina crucible using metallic lithium as the reducing agent and lithium chloride molten salt as the reaction medium at 923 K.The study assessed the effects of lithium thermochemical reduction and electrolytic reduction of ZnO.The volatilization behavior of metal oxides in molten salts,the equivalent of a reducing agent,reduction time,amount of molten salt,stirring time,and the method of reduction feed were investigated for their impacts on the reduction yield and product composition.X-ray powder diffraction(XRD)analysis of the products showed that lithium reduction of ZnO not only produced metallic Zn but also formed a LiZn alloy.Electrolytic reduction can be used to obtain the metallic Zn product by controlling the potential below-2.2 V(vs Ag/Ag^(+)).Moreover,sintered oxides and higher electrode potentials could enhance the efficiency of electrolysis.Under the optimal reaction conditions determined experimentally,the lithium reduction experiment achieved a yield of 77.2%after a 12-h test,and the electrolytic reduction reached a yield of 85.4%after a 6-h test.
文摘The electrochemical conversion of toxic nitrite(NO_(2)-)is a promising approach for the simultaneous removal of nitrogen contaminants and synthesis of ammonia(NH_(3)).In this study,we present the Er-doping-induced electronic modulation of CoP integrated with nitrogen-doped carbon(CN)nanosheets supported on a titanium mesh(Er-CoP@NC/TM)for the electrocatalytic NO_(2)-reduction reaction(eNO_(2)-RR)for NH_(3)synthesis.The catalyst demonstrates a high Faraday efficiency of 97.08±2.22%and a high yield of 2087.60±17.10μmol h^(-1)cm^(-2)for NH_(3)production.Characterization and theoretical calculations revealed that Er-doping facilitated the electronic modulation of CoP in Er-CoP@NC/TM,which regulated the adsorption behaviors of intermediates and was the rate-limiting step for the eNO_(2)-RR,thereby enhancing the electrocatalytic performance.Quenching experiments and electron paramagnetic resonance tests suggest that both direct electrocatalytic reduction by active hydrogen and electron transfer are critical for the eNO_(2)-RR for NH_(3)synthesis.Furthermore,Er-CoP@NC/TM exhibited high performance across a wide range of NO_(2)-concentrations(0.05-0.1 mol L^(-1))and pH values(4-13).In addition,the catalyst demonstrated strong resistance to anions and a long cycle life in simulated wastewater environments.This study offers a powerful approach for the remediation of NO_(2)-wastewater and recovery of valuable inorganic compounds.
基金financially supported by the National Natural Science Foundation of China (No.22372057)Yunnan Fundamental Research Projects (No.202301AT070059)+2 种基金the Natural Science Foundation of Hunan Province (No.2023JJ30121)the Natural Science Foundation of Changsha (No.KQ2208259)the Fundamental Research Funds for the Central Universities (No.202044011)。
文摘Perovskite oxides have shown great potential application in fuel cells due to the unique crystal structures and tunable composition as well as effective capability toward the oxygen reduction reaction(ORR),whereas the investigation on the electrocatalytic performance of perovskite oxides toward the two-electron ORR to H_(2)O_(2)production remains very limited.Herein,a facile synthetic method has been developed to prepare La_(2)Sn_(2)O_(7)@La-doped ZnSnO_(3)heterostructures comprising of amorphous La_(2)Sn_(2)O_(7)and crystalline La-doped ZnSnO_(3).The optimal La_(2)Sn_(2)O_(7)@Ladoped ZnSnO_(3)heterostructures catalyst exhibits a significantly improved two-electron ORR performance to H_(2)O_(2)production with onset potential of 0.77 V and large current density of 2.51 m A.cm^(-2)at 0.1 V compared to ZnSnO_(3)(0.75 V,1.80 m A.cm^(-2),0.11 m A) as well as maintains high H_(2)O_(2)selectivity of 80%,which has been theoretically demonstrated to be contributed to the synergistic effect of amorphous La_(2)Sn_(2)O_(7)and crystalline La-doped ZnSnO_(3).Moreover,high H_(2)O_(2)yield rate of 2.9 m M.h^(-1)at 0.1 V can be achieved with a superior turnover frequency(TOF) of3.31 × 10^(-2)s^(-1)compared to the ZnSnO_(3)catalyst(2.10 × 10^(-2)s^(-1)).This work reveals the great potential of perovskite oxide as promising candidates for the environmentally friendly synthesis of hydrogen peroxide.
基金support from the National Natural Science Foundation of China(Nos.52370100,52000146,and 51978098)China Postdoctoral Science Foundation(No.2020M673351).
文摘Catalytic reduction of nitrate over bimetallic catalysts has emerged as a technology for sustainable treatment of nitrate-containing groundwater.However,the structure of bimetallic has been much less investigated for catalyst optimization.Herein,two main types of Pd-Cu bimetallic nanocrystal structures,heterostructure and intermetallic,were prepared and characterized using high-resolution transmission electron microscopy(HRTEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The results show that two individual Pd and Cu nanocrystals with a mixed interface exist in the heterostructure nanocrystals,while Pd and Cu atoms are uniformly distributed across the intermetallic Pd-Cu nanocrystals.The catalytic nitrate reduction experiments were carried out in a semibatch reactor under constant hydrogen flow.The nitrate conversion rate of the heterostructure Pd-Cu nanocrystals supported onα-Al_(2)O_(3),γ-Al_(2)O_(3),SBA-15,and XC-72R exhibited 3.82-,6.76-,4.28-,2.44-fold enhancements relative to the intermetallic nanocrystals,and the nitrogen and nitrite were the main products for the heterostructure and intermetallic Pd-Cu nanocrystals,respectively.This indicates that the catalytic nitrate reduction over Pd-Cu catalyst is sensitive to the bimetallic structures of the catalysts,and heterostructure bimetallic nanocrystals exhibit better catalytic performances on both the activity and selectivity,which may provide new insights into the design and optimization of catalysts to improve catalytic activity and selectivity for nitrate reduction in water.
基金support from the National Natural Science Foundation of China(Nos.U21A2034 and 21876052)the Guangdong Special Support Plan for Innovation Teams(No.2019BT02L218)+1 种基金the Guangdong Special Support Plan for Young Top-notch Talents(No.2019TQ05L179)the Natural Science Foundation of Guangdong Province,China(No.2021B1515120077)。
文摘Electrochemical nitrate reduction(NO_(3)RR)offers a promising avenue for treating nitrate-contaminated water and recovering ammonia(NH_(3)),yet the complexities of direct electron transfer(DET)and hydrogen atom transfer(HAT)mechanisms crucial for efficiency remain elusive.This study bridges the gap with a combined experimental and theoretical approach,elucidating the impact of catalyst structure on NO3RR pathways.We discover that catalysts favoring strong NO_(3^(-))adsorption and efficient water dissociation were more inclined towards DET,enhancing denitrification.The Fe@Fe_(3)O_(4)/FF cathode,leveraging the synergistic interplay between metallic Fe and Fe_(3)O_(4),excelled in NO3RR via DET,achieving an NH3yield of 0.28 mmol h-1cm-2and a Faradaic efficiency of 95.7%for NH3at-1.6 V(vs.SCE),with minimal nitrite accumulation at 100 mmol/L nitrate.Conversely,the Fe/FF and Fe_(3)O_(4)/CC cathodes showed reduced NH3production and increased nitrite levels,attributed to the lack of Fe_(3)O_(4)and metallic Fe,respectively,resulting in a dominant HAT mechanism.Moreover,Fe@Fe_(3)O_(4)/FF facilitated complete denitrification in real wastewater treatment by harnessing Cl^(-)for electrochemically mediated breakpoint chlorination.This research not only deepens our understanding of NO3RR mechanisms but also paves the way for designing superior nitrate reduction catalysts.
基金supported by the National Key R&D Program of China(No.2021YFA1200201)the Beijing Outstanding Young Scientists Projects(No.BJJWZYJH01201910005018)+1 种基金The Basic Science Center Program for Multiphase Evolution in Hypergravity of the National Natural Science Foundation of China(No.51988101)the National Natural Science Foundation of China(Nos.52071003 and 91860202)。
文摘The photocatalytic reduction of CO_(2)presents a promising avenue for carbon fuel conversion.However,the efficiency of charge utilization remains a critical barrier to industrial applications.In this study,we introduce a tandem design of Bi_(2)WO_(6)-BiOCl with an atomically matched interface,achieving highly efficient photoreduction of CO_(2)to CO.By incorporating WO_(4)^(2-)ions and tuning coordination environment,the(110)facet of BiOCl was in-situ grown on the(200)facet of Bi_(2)WO_(6).Compared to single phases and ball-milling samples,Bi_(2)WO_(6)-BiOCl exhibits a remarkable CO yield of 68.03μmol g^(-1)h^(-1)with a selectivity of 98%.Atomic visualization and coordination analysis confirm the formation of a coherent interface that facilitates charge migration for efficient electron transport.Density functional theory(DFT)calculations and in-situ Fourier transform infrared(FTIR)spectroscopy provide insights into the intrinsic active sites and reaction mechanisms.The proposed lattice engineering strategies offer a new paradigm for the rational design of heterostructures beyond traditional band alignment at the atomic scale.
基金the financial support from the Fundamental Research Funds for the Central Universities(JUSRP122003)the fellowship of China Postdoctoral Science Foundation(2022TQ0123).
文摘Inspired by the aquatic-adapted pit structures of the Cybister beetles that enable high-speed swimming,this study employs warp-knitted technology to fabricate drag-reduction swimwear textiles.Eight distinct fabric morphologies were produced,and a self-developed high-precision dynamic drag measurement device was used to systematically analyze the mechanisms underlying the drag-reduction performance of these biomimetic pit structures.The device incorporates a servomotor,ball screw linkage,and high-precision tension sensor,enabling real-time and accurate detection of fluid drag forces.It effectively overcomes the limitations of traditional indirect measurement methods,including dynamic response lag and insufficient accuracy.Experimental results demonstrate that the hydrophobic small-pit fabric(4^(#))achieves an 84% drag reduction at 400 mm/s,outperforming the control sample(warp-knitted fabric 7^(#)).This significant reduction is attributed to the Cassie state established on the hydrophobic surface,which substantially decreases viscous drag and the microvortices generated by the pit structures,which delay flow separation and effectively minimize pressure drag.Furthermore,small-pit fabrics demonstrate a drag reduction rate 26% to 50% higher than that of large-pit structures,highlighting the critical importance of matching the pit scale to the thickness of the near-wall viscous sublayer for optimal drag reduction.This study establishes a theoretical foundation for the biomimetic design of high-performance drag-reduction swimsuits.The developed drag-measuring device also provides a standardized experimental platform for hydrodynamic studies of flexible materials,supporting a shift from empirical design methodologies to theory-driven approaches in drag-reduction technology and exhibiting significant potential for future advancements.
基金supported by the National Key R&D Program of China(2024YFF0508101)the Fundamental Research Funds for the Beijing Jiaotong University(2024JBMC010)the National Natural Science Foundation of China(52378428).
文摘Due to its high space utilization efficiency and overall advantages,the"integrated station-bridge"design is widely used in high-speed rail stations.However,compared to traditional separated station-bridge structures,the structure-borne noise generated by high-speed trains passing through these stations is more pronounced.To investigate the structure-borne noise radiation characteristics of these station designs,we developed a noise simulation model for the"integrated station-bridge"high-speed railway station and validated its reliability through comparison with test results.Building on this,we implemented the floating track slab between the track structure and the station platform to mitigate structure-borne noise.Furthermore,we examined the factors influencing the noise reduction effectiveness of the floating floor.The results indicated that train passages result in significant structure-borne noise issues in"integrated station-bridge"stations.The maximum sound pressure levels at the waiting hall and platform exceed 70 dB(A).After the implementation of the floating floor,the maximum sound pressure levels on each floor decreased by 11–14 dB(A).Additionally,increasing the thickness of the floating floor and reducing the stiffness of the steel spring bearings both enhanced the noise reduction effectiveness of the floating floor.
基金supported by the National Key Research and Development Program of China(No.2018YFB1501405)the National Natural Science Foundation of China(No.52476185).
文摘SnS has emerged as an attractive catalyst for the electrochemical CO_(2)reduction reaction(CO_(2)RR)to formate,while its long-term operational stability is hindered by the self-reduction of Sn^(2+) and sulfur dissolution.Thus,maintaining high current efficiency across a wide negative potential range to achieve high production rates of formate remains a significant challenge.In this study,we present a heterostructure constructed with SnS and CuS for efficient CO_(2)RR to formate.The SnS-CuS(30)exhibits a remarkable formate Faradaic efficiency(FE_(f))of 93.94%at−1 V vs.reversible hydrogen electrode(RHE)and demonstrates long-term stability for 7.5 h,maintaining high activity(with an average FE_(f)of 85.6%)across a wide negative potential range(from-0.8 to-1.2 V(vs.RHE)).The results reveal that the heterogeneous interface between SnS and CuS mitigates the self-reduction issue of SnS by sacrificing Cu^(2+),highlighting that the true active species is SnS,which effectively resists structural changes during the electrolysis process under the protection of CuS.The synergistic interaction within the CuS and SnS heterostructure,combined with the tendency for electron self-conduction,enables the catalyst to maintain high formate activity and selectivity across a wide potential range.Furthermore,theoretical results further indicate that the incorporation of CuS enhances CO_(2)adsorption and lowers the energy barrier for the formation of formate intermediates.This study inspires the concept of applying protective layers to active species,promoting high selectivity in Sn-based electrocatalysts.
