The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor ...The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion.展开更多
Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru ...Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru has aroused significant concern because of its Pt-like activity and much lower price.However,it’s still a top priority to minimize the Ru loading and pursue the most superior cost performance.展开更多
The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alka...The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alkaline water.Precise control of the electronic structure by heteroatom doping has proven to be efficient for increasing catalytic activity.Nevertheless,both the structural characteristics and the underlying mechanism are not well understood,especially for doping with two different atoms,thus limiting the use of these catalysts.We report the production of phosphorus and nitrogen co-doped hollow carbon nanospheres(HCNs)by the copolymerization of pyrrole and aniline at a Triton X-100 micelle-interface,followed by doping with phytic acid and carbonization.The unique pore structure and defect-rich framework of the HCNs expose numerous active sites.Crucially,the combined effect of graphitic nitrogen and phosphorus-carbon bonds modulate the local electronic structure of adjacent C atoms and facilitates electron transfer.As a res-ult,the HCN carbonized at 1100°C exhibited superior HER activity and an outstanding stability(70 h at a current density of 10 mA cm^(−2))in alkaline water,because of the large number of graphitic nitrogen and phosphorus-carbon bonds.展开更多
Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to thei...Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to their exceptional hydrogen binding energy,exhibit remarkable catalytic activity and long-term stability in the hydrogen evolution reaction(HER).However,the restricted accessibility and exorbitant cost of noble-metal materials pose obstacles to their extensive adoption in industrial contexts.This review investigates strategies aimed at reducing the dependence on noble-metal electrocatalysts and developing a cost-effective alkaline HER catalyst,while considering the principles of sustainable development.The initial discussion covers the fundamental principle of HER,followed by an overview of prevalent techniques for synthesizing catalysts based on noble metals,along with a thorough examination of recent advancements.The subsequent discussion focuses on the strategies employed to improve noble metalbased catalysts,including enhancing the intrinsic activity at active sites and increasing the quantity of active sites.Ultimately,this investigation concludes by examining the present state and future direction of research in the field of electrocatalysis for the HER.展开更多
Transition metal carbides,known as MXenes,particularly Ti_(3)C_(2)T_(x),have been extensively explored as promising materials for electrochemical reactions.However,transition metal carbonitride MXenes with high nitrog...Transition metal carbides,known as MXenes,particularly Ti_(3)C_(2)T_(x),have been extensively explored as promising materials for electrochemical reactions.However,transition metal carbonitride MXenes with high nitrogen content for electrochemical reactions are rarely reported.In this work,transition metal carbonitride MXenes incorporated with Pt-based electrocatalysts,ranging from single atoms to sub-nanometer dimensions,are explored for hydrogen evolution reaction(HER).The fabricated Pt clusters/MXene catalyst exhibits superior HER performance compared to the single-atom-incorporated MXene and commercial Pt/C catalyst in both acidic and alkaline electrolytes.The optimized sample shows low overpotentials of 28,65,and 154 mV at a current densities of 10,100,and 500 m A cm^(-2),a small Tafel slope of 29 m V dec^(-1),a high mass activity of 1203 mA mgPt^(-1)and an excellent turnover frequency of 6.1 s^(-1)in the acidic electrolyte.Density functional theory calculations indicate that this high performance can be attributed to the enhanced active sites,increased surface functional groups,faster charge transfer dynamics,and stronger electronic interaction between Pt and MXene,resulting in optimized hydrogen absorption/desorption toward better HER.This work demonstrates that MXenes with a high content of nitrogen may be promising candidates for various catalytic reactions by incorporating single atoms or clusters.展开更多
The issues of fossil energy shortage and environmental pollution caused by the excessive consumption of conventional fossil fuels necessitates the exploration of renewable and clean energy sources such as hydrogen,whi...The issues of fossil energy shortage and environmental pollution caused by the excessive consumption of conventional fossil fuels necessitates the exploration of renewable and clean energy sources such as hydrogen,which is viable alternative to traditional energy sources in view of its high energy density and nonpolluting nature.In this regard,photocatalytic technology powered by inexhaustible solar energy is an ideal hydrogen production method.The recently developed copper-and zinc-based multinary metal sulfide(MMS)semiconductor photocatalysts exhibit the advantages of suitable bandgap,wide light-harvesting range,and flexible elemental composition,thus possessing great potential for achieving considerable photocatalytic hydrogen evolution(PHE)performance.Despite great progress has been achieved,the current photocatalysts still cannot meet the commercial application demands,which highlights the mechanisms understanding and optimization strategies for efficient PHE.Herein,the basic mechanisms of PHE,and effective optimization strategies are firstly introduced.Afterwards,the research process and the performance of copper-and zinc-based MMS photocatalysts,are thoroughly reviewed.Finally,the unresolved issues,and challenges hindering the achievement of overall water splitting have been discussed.展开更多
Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a b...Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a binary nanophotocatalyst fabricated by blending two polymers,PS-PEG5(PS)and PBT-PEG5(PBT),with matched absorption and emission spectra,enabling a Forster resonance energy transfer(FRET)process for enhanced photocatalysis.These heterostructure nanophotocatalysts are processed using a facile and scalable flash nanoprecipitation(FNP)technique with precious kinetic control over binary nanoparticle formation.The resulting nanoparticles exhibit an exceptional photocatalytic hydrogen evolution rate up to 65 mmol g^(-1) h^(-1),2.5 times higher than that single component nanoparticles.Characterizations through fluorescence spectra and transient absorption spectra confirm the hetero-energy transfer within the binary nanoparticles,which prolongs the excited-state lifetime and extends the namely“effective exciton diffusion length”.Our finding opens new avenues for designing efficient organic photocatalysts by improving exciton migration.展开更多
High-entropy alloys(HEAs)have emerged as promising catalysts for the hydrogen evolution reaction(HER)due to their compositional diversity and synergistic effects.In this study,machine learning-accelerated density func...High-entropy alloys(HEAs)have emerged as promising catalysts for the hydrogen evolution reaction(HER)due to their compositional diversity and synergistic effects.In this study,machine learning-accelerated density functional theory(DFT)calculations were employed to assess the catalytic performance of PtPd-based HEAs with the formula PtPdXYZ(X,Y,Z=Fe,Co,Ni,Cu,Ru,Rh,Ag,Au;X≠Y≠Z).Among 56 screened HEA(111)surfaces,PtPdRuCoNi(111)was identified as the most promising,with adsorption energies(E_(ads))between−0.50 and−0.60 eV and high d-band center of−1.85 eV,indicating enhanced activity.This surface showed the hydrogen adsorption free energy(ΔG_(H^(*)))of−0.03 eV for hydrogen adsorption,outperforming Pt(111)by achieving a better balance between adsorption and desorption.Machine learning models,particularly extreme gradient boosting regression(XGBR),significantly reduced computational costs while maintaining high accuracy(root-mean-square error,RMSE=0.128 eV).These results demonstrate the potential of HEAs for efficient and sustainable hydrogen production.展开更多
Pt-based nanocatalysts offer excellent prospects for various industries.However,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable challenge.In this s...Pt-based nanocatalysts offer excellent prospects for various industries.However,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable challenge.In this study,nanocatalysts with ultralow Pt content,excellent performance,and carbon black as support were prepared through in-situ synthesis.These~2-nm particles uniformly and stably dispersed on carbon black because of the strong s-p-d orbital hybridizations between carbon black and Pt,which suppressed the agglomeration of Pt ions.This unique structure is beneficial for the hydrogen evolution reaction.The catalysts exhibited remarkable catalytic activity for hydrogen evolution reaction,exhibiting a potential of 100 mV at 100 mA·cm^(-2),which is comparable to those of commercial Pt/C catalysts.Mass activity(1.61 A/mg)was four times that of a commercial Pt/C catalyst(0.37 A/mg).The ultralow Pt loading(6.84wt%)paves the way for the development of next-generation electrocatalysts.展开更多
The utilization of nickel-based catalysts as alternatives to expensive platinum-based(Pt-based)materials for the hydrogen evolution reaction in acidic electrolytes has attracted considerable attention due to their pot...The utilization of nickel-based catalysts as alternatives to expensive platinum-based(Pt-based)materials for the hydrogen evolution reaction in acidic electrolytes has attracted considerable attention due to their potential for enabling cost-effective industrial applications.However,the unsatisfied cyclic stability and electrochemical activity limit their further application.In this work,nickel-molybdenum(Ni-Mo)alloy catalysts were successfully synthesized through a comprehensive process including electrodeposition,thermal annealing,and electrochemical activation.Owing to the synergistic interaction of molybdenum trinickelide(Ni_(3)Mo)and molybdenum dioxide(MoO_(2))in Ni-Mo alloy,the catalyst display superior overall electrochemical properties.A low overpotential of 86 mV at 10 mA/cm^(2)and a Tafel slope of 74.0 mV/dec in 0.5 mol/L H_(2)SO_(4)solution can be achieved.Notably,remarkable stability with negligible performance degradation even after 100 h could be maintained.This work presents a novel and effective strategy for the design and fabrication of high-performance,non-precious metal electrocatalysts for acidic water electrolysis.展开更多
Elemental doping is an effective strategy for tuning the band structure of graphite carbon nitride(CN)to enhance its photocatalytic performance.In this study,sodium(Na)and oxygen(O)co-doped carbon nitride(Na/O-CN_(x),...Elemental doping is an effective strategy for tuning the band structure of graphite carbon nitride(CN)to enhance its photocatalytic performance.In this study,sodium(Na)and oxygen(O)co-doped carbon nitride(Na/O-CN_(x),x=1.0,2.0,3.0,4.0)was synthesized via solid-phase reaction of sodium citrate(NaCA)and pure CN powder in the Teflon-sealed autoclave under air conditions at 180℃.Surface area of Na/O-CN_(3.0) is measured to be 18.8 m^(2)/g,increasing by 60.7%compared to that of pure CN(11.7 m^(2)/g).Bandgap energy of Na/O-CN_(3.0) is determined to be 2.68 eV,marginally lower than that of pure CN(2.70 eV),thereby enhancing its capacity for sunlight absorption.Meanwhile,the incorporation of Na and O atoms into Na/O-CN_(x) is found to effectively reduce recombination rates of photogenerated electron-hole pairs.As a result,Na/O-CN_(x) samples exhibit markedly enhanced photocatalytic hydrogen evolution activity under visible light irradiation.Notably,the optimal Na/O-CN_(3.0) sample achieves a photocatalytic hydrogen production rate of 103.2μmol·g^(–1)·h^(–1),which is 8.2 times greater than that of pure CN(11.2μmol·g^(–1)·h^(–1)).Furthermore,a series of Na/O-CN_(x)-yO_(2)(y=0,20%,40%,60%,80%,100%)samples were prepared by modulating the oxygen content within reaction atmosphere.The catalytic performance evaluations reveal that the incorporation of both Na and O atoms in Na/O-CN_(3.0) enhances photocatalytic activity.This study also introduces novel methodologies for synthesis of metal atom-doped CN materials at lower temperature,highlighting the synergistic effect of Na and O atoms in photocatalytic hydrogen production of Na/O-CN_(x) samples.展开更多
Negatively charged open-framework metal sulfides(NOSs),taking advantages of the characteristics of excellent visible light absorption,easily exchanged cations,and abundant active sites,hold significant promise as high...Negatively charged open-framework metal sulfides(NOSs),taking advantages of the characteristics of excellent visible light absorption,easily exchanged cations,and abundant active sites,hold significant promise as highly efficient photocatalysts for hydrogen evolution.However,their applications in photocatalytic hydrogen evolution(PHE)are infrequently documented and the corresponding photocatalytic mechanism has not yet been explored.Herein,we excavated a novel NOS photocatalyst of(Me_(2)NH_(2))_(6)In_(10)S_(18)(MIS)with a three-dimensional(3D)structure,and successfully incorporated divalent Co(Ⅱ)and metal Co(0)into its cavities via the convenient cation exchange-assisted approach to regulate the critical steps of photocatalytic reactions.As the introduced Co(0)allows for more efficient light utilization and adroitly surficial hydrogen desorption,and meanwhile acts as the‘electron pump’for rapid charge transfer,Co(0)-modified MIS delivers a surprising PHE activity in the initial stage of photocatalysis.With the prolonging of illumination,metal Co(0)gradually escapes from MIS framework,resulting in the decline of PHE performance.By stark contrast,the incorporated Co(Ⅱ)can establish a strong interaction with MIS framework,and simultaneously capture photogenerated electrons from MIS to produce Co(0),which constructs a stable photocatalytic system as well as provides additional channels for spatially separating photogenerated carriers.Thus,Co(Ⅱ)-modified MIS exhibits a robust and highly stable PHE activity of~4944μmol/g/h during the long-term photocatalytic reactions,surpassing most of the previously reported In–S framework photocatalysts.This work represents a breakthrough in the study of PHE performance and mechanism of NOS-based photocatalysts,and sheds light on the design of vip confined NOS-based photocatalysts towards high-efficiency solar-to-chemical energy conversion.展开更多
The integration of machine learning and electrocatalysis presents nota ble advancements in designing and predicting the performance of chiral materials for hydrogen evolution reactions(HER).This study utilizes theoret...The integration of machine learning and electrocatalysis presents nota ble advancements in designing and predicting the performance of chiral materials for hydrogen evolution reactions(HER).This study utilizes theoretical calculations and machine learning techniques to assess the HER performance of both chiral and achiral M-N-SWCNTs(M=In,Bi,and Sb)single-atom catalysts(SACs).The stability preferences of metal atoms are dependent on chirality when interacting with chiral SWCNTs.The HER activity of the right-handed In-N-SWCNT is 5.71 times greater than its achiral counterpart,whereas the left-handed In-N-SWCNT exhibits a 5.12-fold enhancement.The calculated hydrogen adsorption free energy for the right-handed In-N-SWCNT reaches as low as-0.02 eV.This enhancement is attributed to the symmetry breaking in spin density distribution,transitioning from C_(2V)in achiral SACs to C_(2)in chiral SACs,which facilitates active site transfer and enhances local spin density.Right-handed M-N-SWCNTs exhibit superiorα-electron separation and transport efficiency relative to left-handed variants,owing to the chiral induced spin selectivity(CISS)effect,with spin-upα-electron density reaching 3.43×10^(-3)e/Bohr^(3)at active sites.Machine learning provides deeper insights,revealing that the interplay of weak spatial electronic effects and appropriate curvature-chirality effects significantly enhances HER performance.A weaker spatial electronic effect correlates with higher HER activity,larger exchange current density,and higher turnover frequency.The curvature-chirality effect undersco res the influence of intrinsic structures on HER performance.These findings offer critical insights into the role of chirality in electrocatalysis and propose innovative approaches for optimizing HER through chirality.展开更多
Constructing clus ter heterostructures with strongly coupled interfaces is of great importance to accelerating the catalytic reactions that involve multiple intermediates.Herein,a strongly coupled cluster heterostruct...Constructing clus ter heterostructures with strongly coupled interfaces is of great importance to accelerating the catalytic reactions that involve multiple intermediates.Herein,a strongly coupled cluster heterostructure composed of platinum and molybdenum carbide(Pt@Mo_(2)C)derived from polyoxometalate clusters is designed to achieve excellent alkaline hydrogen evolution reaction.The Pt@Mo_(2)C cluster exhibits strong electronic interactions between Pt and Mo_(2)C,working together to facilitate the H_(2)O dissociation by concurrently binding intermediates(Pt-H*and Mo-OH*),thus accelerating the kinetics of the rate-determining Volmer step.Theoptimized Pt@Mo_(2)C exhibits a high mass activity of12.1 A·mgpt^(-1),19.2 times higher than that of 20%Pt/C in alkaline media.Moreover,it can be stabilized at a current density of 100 mA·cm^(-2)for more than 200 h.This work demonstrated the superiority of the cluster heterostructures and co-catalytic effect towards the development of highly efficient electrocatalysts.展开更多
As hydrogen energy technologies gain momentum,the role of renewable energy in facilitating sustainable hydrogen production is becoming increasingly critical.As a hydrogen production method,water electrolysis has attra...As hydrogen energy technologies gain momentum,the role of renewable energy in facilitating sustainable hydrogen production is becoming increasingly critical.As a hydrogen production method,water electrolysis has attracted much attention from researchers due to its operational simplicity,the high purity of the hydrogen generated,and its potential for achieving zero carbon emissions throughout the process.Numerous studies has been manipulated on platinum(Pt)-based catalysts,which exhibit superior performance in hydrogen evolution reactions.Within this category,Pt nanoclusters stand out due to their unique attributes,such as quantum size effects and unique coordination environments.These features enable them to outperform both Pt metal atoms and nanoparticles in hydrogen evolution reactions regarding activity and stability.Here,we primarily delve into the reaction mechanisms underlying Pt nanocluster-based hydrogen catalysts,with particular emphasis on the interactions between the metal catalysts and their associated support materials.We provide an exhaustive summary of the strategies employed in the synthesis,the structural analyses conducted,and the performance metrics observed for Pt nanocluster catalysts when paired with various supporting materials.In closing,we explore the future potential and challenges facing Pt nanocluster-based catalysts in the context of industrial water electrolysis,along with emerging avenues for their design and optimization.展开更多
Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a...Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a series of Schreibersite-type intermetallic compounds,particularly Mo_(2)Fe_(0.8)Ru_(0.2)P,are synthesized through high-temperature solid-phase synthesis.Experimental results demonstrate that the integration of Ru significantly improves the kinetics of proton adsorption and desorption during the hydrogen evolution reaction(HER).Additionally,density functional theory(DFT)calculations and X-ray absorption near edge structure(XANES)analyses effectively corroborate the pronounced d-orbital hybridization of Fe within the structure,which facilitates the transfer of hydroxide ions and the maintenance of material durability during alkaline HER processes.Remarkably,Mo_(2)Fe_(0.8)Ru_(0.2)P exhibits superior alkaline HER activity,characterized by an overpotential of merely 48 mV at a current density of 10 mA cm^(-2).After prolonged operation of 1000 h at high current densities(1.1 A cm^(-2)),the activity decline remains minimal,under 4%(with overpotential increasing from 258 mV to 268 mV).These results demonstrate the potential of strategically combining metallic elements to design high-performance industrial-grade electrocatalysts.展开更多
The activity of photocatalysts can be significantly regulated by designing micro-scale interfacial heterojunctions. The present study demonstrates the skillful construction of a graphdiyne/Sr_(2)Co_(2)O_(5) S-scheme h...The activity of photocatalysts can be significantly regulated by designing micro-scale interfacial heterojunctions. The present study demonstrates the skillful construction of a graphdiyne/Sr_(2)Co_(2)O_(5) S-scheme heterojunction, exhibiting exceptional stability, excellent proton adsorption, and remarkable photocatalytic activity. On the basis of in-situ XPS and calculation of work function, it is proved that the electron migration path between the interface of graphdiyne and Sr_(2)Co_(2)O_(5) conforms to the S-scheme heterojunction mechanism. The recombination rate of photogenerated carriers is significantly reduced by virtue of the synergistic effect of the internal electric field and band edge bending while preserving the inherent redox ability of the materials. The strong coupling between layered graphdiyne and hierarchical flower-like Sr_(2)Co_(2)O_(5) effectively enhances the specific surface area of graphdiyne/Sr_(2)Co_(2)O_(5) heterojunction, thereby facilitating H2O pre-adsorption. Combined with experiments and DFT calculations, it was found that both graphdiyne and Sr_(2)Co_(2)O_(5) have a direct band gap, which makes their electronic transitions without the assistance of phonons, thus improving the efficiency of solar energy conversion. This study offers insights into the potential application of graphdiyne and metal oxides in the field of photocatalytic hydrogen evolution.展开更多
The effects of seemingly inert alkali metal(AM)cations on the electrocatalytic activity of electrode materials towards reactions essential for energy provision have become the emphasis of substantial research efforts ...The effects of seemingly inert alkali metal(AM)cations on the electrocatalytic activity of electrode materials towards reactions essential for energy provision have become the emphasis of substantial research efforts in recent years.The hydrogen and oxygen evolution reactions during alkaline water electrolysis and the oxygen electro-reduction taking place in fuel cells are of particular importance.There is no universal theory explaining all the details of the AM cation effect in electrocatalysis.For example,it remains unclear how“spectator”AM-cations can change the kinetics of electrocatalytic reactions often more significantly than the modifications of the elec-trode structure and composition.This situation originates partly from a lack of systematic experimental and theoretical studies of this phenomenon.The present work exploits impedance spectroscopy to investigate the influence of the AM cations on the mechanism of the hydrogen evolution reaction at Pt microelectrodes.The activity follows the trend:Li^(+)≥Na^(+)≥K^(+)≥Cs^(+),where the highest activity corresponds to 0.1 M LiOH electrolytes at low overpotentials.We demonstrate that the nature of the AM cations also changes the relative contribution of the Volmer–Heyrovsky and Volmer–Tafel mechanisms to the overall reaction,with the former being more important for LiOH electrolytes.Our density functional theory-based thermodynamics and molecular dynamics calculations support these findings.展开更多
Heterojunction engineering is considered as one of the most effective methods to improve the hydrogen production performance of photocatalysts.In this study,a green,simple and gentle method was used to deposit tiny Ni...Heterojunction engineering is considered as one of the most effective methods to improve the hydrogen production performance of photocatalysts.In this study,a green,simple and gentle method was used to deposit tiny Ni S onto CTF-ES_(200)under xenon lamp irradiation to form heterostructures.The experimental results show that the hydrogen production rate of the synthesized Ni S/CTF-ES_(200)is as high as 22.98mmol g^(-1)h^(-1),showing a higher photocatalytic hydrogen production rate compared to other Ni S-loaded nonmetallic semiconductor materials,which is also much higher than that of pure CTF-ES_(200).The interface electric field(IEF)in this p-n heterojunction leads to an accumulation of photoelectrons on the conduction band of CTF-ES_(200),which makes CTF-ES_(200)to keep a high reductiveness for the hydrogen evolution reaction(HER),and significantly improve the separation efficiency of photoelectrons and holes.Furthermore,XPS and EXAFS data show that an efficient electron transport channel is constructed through the formation of Ni-N bond,which further accelerates the interface carrier transport efficiency.This study provides an effective idea for the preparation of highly efficient heterojunction photocatalysts.展开更多
Alkaline electrolytic hydrogen production has emerged as one of the most practical methods for industrial-scale hydrogen production.However,the initial hydrolysis dissociation in alkaline media impedes the hydrogen ev...Alkaline electrolytic hydrogen production has emerged as one of the most practical methods for industrial-scale hydrogen production.However,the initial hydrolysis dissociation in alkaline media impedes the hydrogen evolution reaction(HER)kinetics of commercial catalysts.To overcome this limitation,this study focuses on the development of a highly efficient electrocatalyst for alkaline HER.Ni-based intermetallic compounds exhibit remarkable catalytic activity for HER,with the NiMo alloy being among the most active catalysts in alkaline environments.Here,we designed and fabricated self-supported multiscale porous NiZn/NiMo intermetallic compounds on a metal foam substrate using a versatile dealloying method.The resulting electrode exhibits excellent HER activity,achieving an overpotential of just 204 mV at 1000 mA/cm^(2),and dem-onstrates robust long-term catalytic stability,maintaining performance at 100 mA/cm^(2) for 400 h in an alkaline electrolyte.Thesefindings underscore the potential of nanosized intermetallic compounds fabricated via a dealloying approach to deliver exceptional catalytic performance for alkaline water electrolysis.展开更多
文摘The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion.
基金supported by the Development Project of Youth Innovation Team in Shandong Colleges and Universities(No.2019KJC031)the Natural Science Foundation of Shandong Province(Nos.ZR2019MB064,ZR2021MB122 and ZR2022MB137)the Doctoral Program of Liaocheng University(No.318051608).
文摘Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru has aroused significant concern because of its Pt-like activity and much lower price.However,it’s still a top priority to minimize the Ru loading and pursue the most superior cost performance.
基金financially supported by the project of the National Natural Science Foundation of China(52322203)the Key Research and Development Program of Shaanxi Province(2024GHZDXM-21)。
文摘The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alkaline water.Precise control of the electronic structure by heteroatom doping has proven to be efficient for increasing catalytic activity.Nevertheless,both the structural characteristics and the underlying mechanism are not well understood,especially for doping with two different atoms,thus limiting the use of these catalysts.We report the production of phosphorus and nitrogen co-doped hollow carbon nanospheres(HCNs)by the copolymerization of pyrrole and aniline at a Triton X-100 micelle-interface,followed by doping with phytic acid and carbonization.The unique pore structure and defect-rich framework of the HCNs expose numerous active sites.Crucially,the combined effect of graphitic nitrogen and phosphorus-carbon bonds modulate the local electronic structure of adjacent C atoms and facilitates electron transfer.As a res-ult,the HCN carbonized at 1100°C exhibited superior HER activity and an outstanding stability(70 h at a current density of 10 mA cm^(−2))in alkaline water,because of the large number of graphitic nitrogen and phosphorus-carbon bonds.
基金financial support by the National Natural Science Foundation of China(No.52102241)Doctor of Suzhou University Scientific Research Foundation(Nos.2022BSK019,2020BS015)+2 种基金the Primary Research and Development Program of Anhui Province(No.201904a05020087)the Natural Science Research Project in Universities of Anhui Province in China(Nos.2022AH051386,KJ2021A1114)the Foundation(No.GZKF202211)of State Key Laboratory of Biobased Material and Green Papermaking Qilu University of Technology。
文摘Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to their exceptional hydrogen binding energy,exhibit remarkable catalytic activity and long-term stability in the hydrogen evolution reaction(HER).However,the restricted accessibility and exorbitant cost of noble-metal materials pose obstacles to their extensive adoption in industrial contexts.This review investigates strategies aimed at reducing the dependence on noble-metal electrocatalysts and developing a cost-effective alkaline HER catalyst,while considering the principles of sustainable development.The initial discussion covers the fundamental principle of HER,followed by an overview of prevalent techniques for synthesizing catalysts based on noble metals,along with a thorough examination of recent advancements.The subsequent discussion focuses on the strategies employed to improve noble metalbased catalysts,including enhancing the intrinsic activity at active sites and increasing the quantity of active sites.Ultimately,this investigation concludes by examining the present state and future direction of research in the field of electrocatalysis for the HER.
基金the final support of ARC DP220103045the startup support of KFUPMPrince Sultan University for their support。
文摘Transition metal carbides,known as MXenes,particularly Ti_(3)C_(2)T_(x),have been extensively explored as promising materials for electrochemical reactions.However,transition metal carbonitride MXenes with high nitrogen content for electrochemical reactions are rarely reported.In this work,transition metal carbonitride MXenes incorporated with Pt-based electrocatalysts,ranging from single atoms to sub-nanometer dimensions,are explored for hydrogen evolution reaction(HER).The fabricated Pt clusters/MXene catalyst exhibits superior HER performance compared to the single-atom-incorporated MXene and commercial Pt/C catalyst in both acidic and alkaline electrolytes.The optimized sample shows low overpotentials of 28,65,and 154 mV at a current densities of 10,100,and 500 m A cm^(-2),a small Tafel slope of 29 m V dec^(-1),a high mass activity of 1203 mA mgPt^(-1)and an excellent turnover frequency of 6.1 s^(-1)in the acidic electrolyte.Density functional theory calculations indicate that this high performance can be attributed to the enhanced active sites,increased surface functional groups,faster charge transfer dynamics,and stronger electronic interaction between Pt and MXene,resulting in optimized hydrogen absorption/desorption toward better HER.This work demonstrates that MXenes with a high content of nitrogen may be promising candidates for various catalytic reactions by incorporating single atoms or clusters.
文摘The issues of fossil energy shortage and environmental pollution caused by the excessive consumption of conventional fossil fuels necessitates the exploration of renewable and clean energy sources such as hydrogen,which is viable alternative to traditional energy sources in view of its high energy density and nonpolluting nature.In this regard,photocatalytic technology powered by inexhaustible solar energy is an ideal hydrogen production method.The recently developed copper-and zinc-based multinary metal sulfide(MMS)semiconductor photocatalysts exhibit the advantages of suitable bandgap,wide light-harvesting range,and flexible elemental composition,thus possessing great potential for achieving considerable photocatalytic hydrogen evolution(PHE)performance.Despite great progress has been achieved,the current photocatalysts still cannot meet the commercial application demands,which highlights the mechanisms understanding and optimization strategies for efficient PHE.Herein,the basic mechanisms of PHE,and effective optimization strategies are firstly introduced.Afterwards,the research process and the performance of copper-and zinc-based MMS photocatalysts,are thoroughly reviewed.Finally,the unresolved issues,and challenges hindering the achievement of overall water splitting have been discussed.
基金supported by National Natural Science Foundation of China(NSFC,22338006,92356301,9235630033 and 22375062)Shanghai Municipal Science and Technology Major Project(21JC1401700)+4 种基金Shanghai Pilot Program for Basic Research(22TQ1400100-10)Fundamental Research Funds for the Central UniversitiesShanghai Pujiang Program(22PJ1402400)“Chenguang Program”supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(22CGA32)the Young Elite Scientists Sponsorship Program by CAST(2023QNRC001).
文摘Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a binary nanophotocatalyst fabricated by blending two polymers,PS-PEG5(PS)and PBT-PEG5(PBT),with matched absorption and emission spectra,enabling a Forster resonance energy transfer(FRET)process for enhanced photocatalysis.These heterostructure nanophotocatalysts are processed using a facile and scalable flash nanoprecipitation(FNP)technique with precious kinetic control over binary nanoparticle formation.The resulting nanoparticles exhibit an exceptional photocatalytic hydrogen evolution rate up to 65 mmol g^(-1) h^(-1),2.5 times higher than that single component nanoparticles.Characterizations through fluorescence spectra and transient absorption spectra confirm the hetero-energy transfer within the binary nanoparticles,which prolongs the excited-state lifetime and extends the namely“effective exciton diffusion length”.Our finding opens new avenues for designing efficient organic photocatalysts by improving exciton migration.
基金the Second Century Fund(C2F),Chulalongkorn UniversityThailand Science Research and Innovation Fund Chulalongkorn University(No.IND_FF_68_054_2100_009)National Science and Technology Development Agency,Thailand,Hub of Knowledge funding,and the Mid-Career Research Grant 2024,National Research Council of Thailand(No.N42A670295).
文摘High-entropy alloys(HEAs)have emerged as promising catalysts for the hydrogen evolution reaction(HER)due to their compositional diversity and synergistic effects.In this study,machine learning-accelerated density functional theory(DFT)calculations were employed to assess the catalytic performance of PtPd-based HEAs with the formula PtPdXYZ(X,Y,Z=Fe,Co,Ni,Cu,Ru,Rh,Ag,Au;X≠Y≠Z).Among 56 screened HEA(111)surfaces,PtPdRuCoNi(111)was identified as the most promising,with adsorption energies(E_(ads))between−0.50 and−0.60 eV and high d-band center of−1.85 eV,indicating enhanced activity.This surface showed the hydrogen adsorption free energy(ΔG_(H^(*)))of−0.03 eV for hydrogen adsorption,outperforming Pt(111)by achieving a better balance between adsorption and desorption.Machine learning models,particularly extreme gradient boosting regression(XGBR),significantly reduced computational costs while maintaining high accuracy(root-mean-square error,RMSE=0.128 eV).These results demonstrate the potential of HEAs for efficient and sustainable hydrogen production.
基金financially supported by the National Natural Science Foundation of China(No.5217042069)the Young Elite Scientist Sponsorship Program by China Association for Science and Technology(CAST)(No.YESS20200103)the Fundamental Research Funds for the Central Universities(No.265QZ2022004)。
文摘Pt-based nanocatalysts offer excellent prospects for various industries.However,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable challenge.In this study,nanocatalysts with ultralow Pt content,excellent performance,and carbon black as support were prepared through in-situ synthesis.These~2-nm particles uniformly and stably dispersed on carbon black because of the strong s-p-d orbital hybridizations between carbon black and Pt,which suppressed the agglomeration of Pt ions.This unique structure is beneficial for the hydrogen evolution reaction.The catalysts exhibited remarkable catalytic activity for hydrogen evolution reaction,exhibiting a potential of 100 mV at 100 mA·cm^(-2),which is comparable to those of commercial Pt/C catalysts.Mass activity(1.61 A/mg)was four times that of a commercial Pt/C catalyst(0.37 A/mg).The ultralow Pt loading(6.84wt%)paves the way for the development of next-generation electrocatalysts.
基金supported by the National Natural Science Foundation of China(22179138).
文摘The utilization of nickel-based catalysts as alternatives to expensive platinum-based(Pt-based)materials for the hydrogen evolution reaction in acidic electrolytes has attracted considerable attention due to their potential for enabling cost-effective industrial applications.However,the unsatisfied cyclic stability and electrochemical activity limit their further application.In this work,nickel-molybdenum(Ni-Mo)alloy catalysts were successfully synthesized through a comprehensive process including electrodeposition,thermal annealing,and electrochemical activation.Owing to the synergistic interaction of molybdenum trinickelide(Ni_(3)Mo)and molybdenum dioxide(MoO_(2))in Ni-Mo alloy,the catalyst display superior overall electrochemical properties.A low overpotential of 86 mV at 10 mA/cm^(2)and a Tafel slope of 74.0 mV/dec in 0.5 mol/L H_(2)SO_(4)solution can be achieved.Notably,remarkable stability with negligible performance degradation even after 100 h could be maintained.This work presents a novel and effective strategy for the design and fabrication of high-performance,non-precious metal electrocatalysts for acidic water electrolysis.
基金National Natural Science Foundation of China(21806023)Natural Science Foundation of Hunan Province(2021JJ40199)+2 种基金Education Department Foundation of Hunan Province(20C0813)Hunan University of Science and Technology Fundamental Research FundsPostgraduate Scientific Research Innovation Project of Hunan Province(CX20240877)。
文摘Elemental doping is an effective strategy for tuning the band structure of graphite carbon nitride(CN)to enhance its photocatalytic performance.In this study,sodium(Na)and oxygen(O)co-doped carbon nitride(Na/O-CN_(x),x=1.0,2.0,3.0,4.0)was synthesized via solid-phase reaction of sodium citrate(NaCA)and pure CN powder in the Teflon-sealed autoclave under air conditions at 180℃.Surface area of Na/O-CN_(3.0) is measured to be 18.8 m^(2)/g,increasing by 60.7%compared to that of pure CN(11.7 m^(2)/g).Bandgap energy of Na/O-CN_(3.0) is determined to be 2.68 eV,marginally lower than that of pure CN(2.70 eV),thereby enhancing its capacity for sunlight absorption.Meanwhile,the incorporation of Na and O atoms into Na/O-CN_(x) is found to effectively reduce recombination rates of photogenerated electron-hole pairs.As a result,Na/O-CN_(x) samples exhibit markedly enhanced photocatalytic hydrogen evolution activity under visible light irradiation.Notably,the optimal Na/O-CN_(3.0) sample achieves a photocatalytic hydrogen production rate of 103.2μmol·g^(–1)·h^(–1),which is 8.2 times greater than that of pure CN(11.2μmol·g^(–1)·h^(–1)).Furthermore,a series of Na/O-CN_(x)-yO_(2)(y=0,20%,40%,60%,80%,100%)samples were prepared by modulating the oxygen content within reaction atmosphere.The catalytic performance evaluations reveal that the incorporation of both Na and O atoms in Na/O-CN_(3.0) enhances photocatalytic activity.This study also introduces novel methodologies for synthesis of metal atom-doped CN materials at lower temperature,highlighting the synergistic effect of Na and O atoms in photocatalytic hydrogen production of Na/O-CN_(x) samples.
基金financial supports provided by the Natural Science Foundation of Fujian Province(No.2024J01195)the National Nature Science Foundation of China(No.21905279)+1 种基金Sanming University(Nos.22YG11 and PYT2201)the Education Scientific Research Project of Youth Teachers in the Education Department of Fujian Province(No.JAT220351).
文摘Negatively charged open-framework metal sulfides(NOSs),taking advantages of the characteristics of excellent visible light absorption,easily exchanged cations,and abundant active sites,hold significant promise as highly efficient photocatalysts for hydrogen evolution.However,their applications in photocatalytic hydrogen evolution(PHE)are infrequently documented and the corresponding photocatalytic mechanism has not yet been explored.Herein,we excavated a novel NOS photocatalyst of(Me_(2)NH_(2))_(6)In_(10)S_(18)(MIS)with a three-dimensional(3D)structure,and successfully incorporated divalent Co(Ⅱ)and metal Co(0)into its cavities via the convenient cation exchange-assisted approach to regulate the critical steps of photocatalytic reactions.As the introduced Co(0)allows for more efficient light utilization and adroitly surficial hydrogen desorption,and meanwhile acts as the‘electron pump’for rapid charge transfer,Co(0)-modified MIS delivers a surprising PHE activity in the initial stage of photocatalysis.With the prolonging of illumination,metal Co(0)gradually escapes from MIS framework,resulting in the decline of PHE performance.By stark contrast,the incorporated Co(Ⅱ)can establish a strong interaction with MIS framework,and simultaneously capture photogenerated electrons from MIS to produce Co(0),which constructs a stable photocatalytic system as well as provides additional channels for spatially separating photogenerated carriers.Thus,Co(Ⅱ)-modified MIS exhibits a robust and highly stable PHE activity of~4944μmol/g/h during the long-term photocatalytic reactions,surpassing most of the previously reported In–S framework photocatalysts.This work represents a breakthrough in the study of PHE performance and mechanism of NOS-based photocatalysts,and sheds light on the design of vip confined NOS-based photocatalysts towards high-efficiency solar-to-chemical energy conversion.
基金the full support of the National Natural Science Foundation of China(62071154,51272052 and50902040)the Natural Science Foundation of Heilongjiang Province of China(LH2020B011 and LH2019B006)the Scientific Research Projects of Basic Scientific Research Operational Expenses of Heilongjiang Provincial Colleges and Universities(2021-KYYWF-0171)。
文摘The integration of machine learning and electrocatalysis presents nota ble advancements in designing and predicting the performance of chiral materials for hydrogen evolution reactions(HER).This study utilizes theoretical calculations and machine learning techniques to assess the HER performance of both chiral and achiral M-N-SWCNTs(M=In,Bi,and Sb)single-atom catalysts(SACs).The stability preferences of metal atoms are dependent on chirality when interacting with chiral SWCNTs.The HER activity of the right-handed In-N-SWCNT is 5.71 times greater than its achiral counterpart,whereas the left-handed In-N-SWCNT exhibits a 5.12-fold enhancement.The calculated hydrogen adsorption free energy for the right-handed In-N-SWCNT reaches as low as-0.02 eV.This enhancement is attributed to the symmetry breaking in spin density distribution,transitioning from C_(2V)in achiral SACs to C_(2)in chiral SACs,which facilitates active site transfer and enhances local spin density.Right-handed M-N-SWCNTs exhibit superiorα-electron separation and transport efficiency relative to left-handed variants,owing to the chiral induced spin selectivity(CISS)effect,with spin-upα-electron density reaching 3.43×10^(-3)e/Bohr^(3)at active sites.Machine learning provides deeper insights,revealing that the interplay of weak spatial electronic effects and appropriate curvature-chirality effects significantly enhances HER performance.A weaker spatial electronic effect correlates with higher HER activity,larger exchange current density,and higher turnover frequency.The curvature-chirality effect undersco res the influence of intrinsic structures on HER performance.These findings offer critical insights into the role of chirality in electrocatalysis and propose innovative approaches for optimizing HER through chirality.
基金supported by the National Natural Science Foundation of China(Nos.22171287 and 52303274)Taishan Scholar Project of Shandong Province(No.tsqn202103046)+2 种基金Natural Science Foundation of Shandong Province(No.ZR2022QE175)Young Innovative Science and Technology Support Program for Universities of Shandong Province,P.R.China(Nos.2023KJ280 and 2021KJ014)Fundamental Research Funds for the Central Universities(Nos.24CX07007A and 22CX01002A-1)
文摘Constructing clus ter heterostructures with strongly coupled interfaces is of great importance to accelerating the catalytic reactions that involve multiple intermediates.Herein,a strongly coupled cluster heterostructure composed of platinum and molybdenum carbide(Pt@Mo_(2)C)derived from polyoxometalate clusters is designed to achieve excellent alkaline hydrogen evolution reaction.The Pt@Mo_(2)C cluster exhibits strong electronic interactions between Pt and Mo_(2)C,working together to facilitate the H_(2)O dissociation by concurrently binding intermediates(Pt-H*and Mo-OH*),thus accelerating the kinetics of the rate-determining Volmer step.Theoptimized Pt@Mo_(2)C exhibits a high mass activity of12.1 A·mgpt^(-1),19.2 times higher than that of 20%Pt/C in alkaline media.Moreover,it can be stabilized at a current density of 100 mA·cm^(-2)for more than 200 h.This work demonstrated the superiority of the cluster heterostructures and co-catalytic effect towards the development of highly efficient electrocatalysts.
基金the National Key Research and Development Program of China(No.2022YFB4102000)the National Natural Science Foundation of China(NSFC,Nos.22102018 and 52171201)+4 种基金the Huzhou Science and Technology Bureau(No.2022GZ45)the Hefei National Research Center for Physical Sciences at the Microscale(No.KF2021005)the China Postdoctoral Science Foundation-Funded Project(No.2022M710601)the Huzhou Science and Technology Bureau(No.2023GZ02)the Natural Science Foundation of Sichuan Province(No.24NSFSC5779)。
文摘As hydrogen energy technologies gain momentum,the role of renewable energy in facilitating sustainable hydrogen production is becoming increasingly critical.As a hydrogen production method,water electrolysis has attracted much attention from researchers due to its operational simplicity,the high purity of the hydrogen generated,and its potential for achieving zero carbon emissions throughout the process.Numerous studies has been manipulated on platinum(Pt)-based catalysts,which exhibit superior performance in hydrogen evolution reactions.Within this category,Pt nanoclusters stand out due to their unique attributes,such as quantum size effects and unique coordination environments.These features enable them to outperform both Pt metal atoms and nanoparticles in hydrogen evolution reactions regarding activity and stability.Here,we primarily delve into the reaction mechanisms underlying Pt nanocluster-based hydrogen catalysts,with particular emphasis on the interactions between the metal catalysts and their associated support materials.We provide an exhaustive summary of the strategies employed in the synthesis,the structural analyses conducted,and the performance metrics observed for Pt nanocluster catalysts when paired with various supporting materials.In closing,we explore the future potential and challenges facing Pt nanocluster-based catalysts in the context of industrial water electrolysis,along with emerging avenues for their design and optimization.
基金supported by Research Grants of the NRF(2023R1A2C2003823,RS-2024-00405818)funded by the National Research Foundation under the Ministry of Science,ICT&Future,Korea。
文摘Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a series of Schreibersite-type intermetallic compounds,particularly Mo_(2)Fe_(0.8)Ru_(0.2)P,are synthesized through high-temperature solid-phase synthesis.Experimental results demonstrate that the integration of Ru significantly improves the kinetics of proton adsorption and desorption during the hydrogen evolution reaction(HER).Additionally,density functional theory(DFT)calculations and X-ray absorption near edge structure(XANES)analyses effectively corroborate the pronounced d-orbital hybridization of Fe within the structure,which facilitates the transfer of hydroxide ions and the maintenance of material durability during alkaline HER processes.Remarkably,Mo_(2)Fe_(0.8)Ru_(0.2)P exhibits superior alkaline HER activity,characterized by an overpotential of merely 48 mV at a current density of 10 mA cm^(-2).After prolonged operation of 1000 h at high current densities(1.1 A cm^(-2)),the activity decline remains minimal,under 4%(with overpotential increasing from 258 mV to 268 mV).These results demonstrate the potential of strategically combining metallic elements to design high-performance industrial-grade electrocatalysts.
基金supported by the Excellent Youth Program,Ningxia Hui Autonomous Region Natural Science Foundation Project(No.2022AAC05034)the Ningxia Low-Grade Resource High-Value Utilization and Environmental Chemical Integration Technology Innovation Team Project of Chinathe Innovative Team for Transforming Waste Cooking Oil into Clean Energy and High Value-Added Chemicals of China.
文摘The activity of photocatalysts can be significantly regulated by designing micro-scale interfacial heterojunctions. The present study demonstrates the skillful construction of a graphdiyne/Sr_(2)Co_(2)O_(5) S-scheme heterojunction, exhibiting exceptional stability, excellent proton adsorption, and remarkable photocatalytic activity. On the basis of in-situ XPS and calculation of work function, it is proved that the electron migration path between the interface of graphdiyne and Sr_(2)Co_(2)O_(5) conforms to the S-scheme heterojunction mechanism. The recombination rate of photogenerated carriers is significantly reduced by virtue of the synergistic effect of the internal electric field and band edge bending while preserving the inherent redox ability of the materials. The strong coupling between layered graphdiyne and hierarchical flower-like Sr_(2)Co_(2)O_(5) effectively enhances the specific surface area of graphdiyne/Sr_(2)Co_(2)O_(5) heterojunction, thereby facilitating H2O pre-adsorption. Combined with experiments and DFT calculations, it was found that both graphdiyne and Sr_(2)Co_(2)O_(5) have a direct band gap, which makes their electronic transitions without the assistance of phonons, thus improving the efficiency of solar energy conversion. This study offers insights into the potential application of graphdiyne and metal oxides in the field of photocatalytic hydrogen evolution.
基金the German Research Foundation(DFG)under Germany's excellence strategy-EXC 2089/1-390776260,Germany's excellence cluster“e-conversion”the DFG project BA 5795/6-1.This project has received additional funding from the European Union's Ho-rizon 2020 research and innovation program under grant agreement HERMES No 952184+1 种基金VA acknowledges the National Science Foundation(NSF)support through the NSF CAREER award(Grant No.CBET-1941204)ASB acknowledges financial support from TUM Innovation Network for Artificial Intelligence powered Multifunctional Material Design(ARTEMIS).
文摘The effects of seemingly inert alkali metal(AM)cations on the electrocatalytic activity of electrode materials towards reactions essential for energy provision have become the emphasis of substantial research efforts in recent years.The hydrogen and oxygen evolution reactions during alkaline water electrolysis and the oxygen electro-reduction taking place in fuel cells are of particular importance.There is no universal theory explaining all the details of the AM cation effect in electrocatalysis.For example,it remains unclear how“spectator”AM-cations can change the kinetics of electrocatalytic reactions often more significantly than the modifications of the elec-trode structure and composition.This situation originates partly from a lack of systematic experimental and theoretical studies of this phenomenon.The present work exploits impedance spectroscopy to investigate the influence of the AM cations on the mechanism of the hydrogen evolution reaction at Pt microelectrodes.The activity follows the trend:Li^(+)≥Na^(+)≥K^(+)≥Cs^(+),where the highest activity corresponds to 0.1 M LiOH electrolytes at low overpotentials.We demonstrate that the nature of the AM cations also changes the relative contribution of the Volmer–Heyrovsky and Volmer–Tafel mechanisms to the overall reaction,with the former being more important for LiOH electrolytes.Our density functional theory-based thermodynamics and molecular dynamics calculations support these findings.
基金financially supported by the National Natural Science Foundation of China(No.22271022)the Science and Technology Development Planning of Jilin Province(No.YDZJ202201ZYTS342)supported by the China Scholarship Council(CSC,No.201802335014)。
文摘Heterojunction engineering is considered as one of the most effective methods to improve the hydrogen production performance of photocatalysts.In this study,a green,simple and gentle method was used to deposit tiny Ni S onto CTF-ES_(200)under xenon lamp irradiation to form heterostructures.The experimental results show that the hydrogen production rate of the synthesized Ni S/CTF-ES_(200)is as high as 22.98mmol g^(-1)h^(-1),showing a higher photocatalytic hydrogen production rate compared to other Ni S-loaded nonmetallic semiconductor materials,which is also much higher than that of pure CTF-ES_(200).The interface electric field(IEF)in this p-n heterojunction leads to an accumulation of photoelectrons on the conduction band of CTF-ES_(200),which makes CTF-ES_(200)to keep a high reductiveness for the hydrogen evolution reaction(HER),and significantly improve the separation efficiency of photoelectrons and holes.Furthermore,XPS and EXAFS data show that an efficient electron transport channel is constructed through the formation of Ni-N bond,which further accelerates the interface carrier transport efficiency.This study provides an effective idea for the preparation of highly efficient heterojunction photocatalysts.
基金Taishan Scholar Project of Shandong Province(No.tsqn202306226)Natural Science Foundation of Shandong Prov-ince(No.ZR2023ME155)+1 种基金The project of“20 Items of University”of Jinan(No.202228046)Luzhou Municipal Science and Technol-ogy Plan Project(Nos.2024JYJ016 and 2024JYJ018).
文摘Alkaline electrolytic hydrogen production has emerged as one of the most practical methods for industrial-scale hydrogen production.However,the initial hydrolysis dissociation in alkaline media impedes the hydrogen evolution reaction(HER)kinetics of commercial catalysts.To overcome this limitation,this study focuses on the development of a highly efficient electrocatalyst for alkaline HER.Ni-based intermetallic compounds exhibit remarkable catalytic activity for HER,with the NiMo alloy being among the most active catalysts in alkaline environments.Here,we designed and fabricated self-supported multiscale porous NiZn/NiMo intermetallic compounds on a metal foam substrate using a versatile dealloying method.The resulting electrode exhibits excellent HER activity,achieving an overpotential of just 204 mV at 1000 mA/cm^(2),and dem-onstrates robust long-term catalytic stability,maintaining performance at 100 mA/cm^(2) for 400 h in an alkaline electrolyte.Thesefindings underscore the potential of nanosized intermetallic compounds fabricated via a dealloying approach to deliver exceptional catalytic performance for alkaline water electrolysis.
