The preparation and application of supported gold and copper catalysts are fundamentally and practically very important.Herein,we confirm that the Au-Cu promoted In_(2)O_(3) catalyst demonstrates a significant electro...The preparation and application of supported gold and copper catalysts are fundamentally and practically very important.Herein,we confirm that the Au-Cu promoted In_(2)O_(3) catalyst demonstrates a significant electronic metal-support interaction(EMSI),which plays a critical role in CO_(2) hydrogenation to methanol and leads to significantly improved activity,compared to the mono-metallic Au and Cu promoted In_(2)O_(3)catalysts.This interaction arises from electron transfer between the oxygen deficient In_(2)O_(3) support and the bimetallic clusters,rendering both Au and Cu clusters positively charged.The presence of Cu^(3+)stabilizes and optimizes the content of oxygen vacancies,leading to a more pronounced positive charge on Au clusters(Au^(3+)).The ability to activate H_(2) is thus enhanced.CO adsorption on Au-Cu/In_(2)O_(3) is also stronger than Au/In_(2)O_(3).This results in higher methanol selectivity of Au-Cu/In_(2)O_(3),with which CO hydrogenation pathway is taken for CO_(2) hydrogenation to methanol.The enhanced H_(2) activation and stronger CO adsorption over Au-Cu/In_(2)O_(3) are key factors in boosting the activity for methanol formation from CO_(2)hvdrogenation.展开更多
Aiming at the problems of insufficient activity and selectivity of Cu-based catalysts in CO_(2)hydrogenation to methanol,Al_(2)O_(3),ZrO_(2)and CeO_(2)modified Cu-ZnO catalysts by the co-precipitation method were prep...Aiming at the problems of insufficient activity and selectivity of Cu-based catalysts in CO_(2)hydrogenation to methanol,Al_(2)O_(3),ZrO_(2)and CeO_(2)modified Cu-ZnO catalysts by the co-precipitation method were prepared,and the influence mechanism of additives on the structure-performance relationship of the catalysts was systematically explored.Through a variety of characterization methods such as XRD,N2 physical adsorption-desorption,TEM,H_(2)-TPR,CO_(2)-TPD and XPS,combined with catalytic performance evaluation experiments,the correlation between the microstructure of catalysts and the reaction performance of CO_(2)hydrogenation to methanol was analyzed in depth.The results show that metal additives significantly improve the performance of catalysts.After the introduction of additives,the specific surface area and pore volume of the catalysts increase,the grain size of Cu decreases,and its dispersion improves.The Ce-modified CZC catalyst exhibited the best performance,with the grain size of CuO as small as 11.41 nm,and the surface oxygen vacancy concentration(OⅡ/OⅠ=3.15)was significantly higher than that of other samples.The reaction performance test shows that under the conditions of 2.8 MPa,8000 h−1 and 280℃,the CO_(2)conversion of the CZC catalyst reached 18.83%,the methanol selectivity was 68.40%,and the methanol yield was 12.88%,all of which are superior to other catalysts.Its excellent performance can be attributed to the fact that CeO_(2)enhances the metal-support interaction,increases the surface basicity,promotes the adsorption and activation of CO_(2),and simultaneously inhibits the reverse water-gas shift side reaction.This study clarifies the structure-activity regulation mechanism of additive modification on Cu-ZnO catalysts,providing a theoretical basis and technical reference for the development of efficient catalysts for CO_(2)hydrogenation to methanol.展开更多
As one of the most promising new energy sources,hydrogen energy is expected to usher in a full-fledged“hydrogen economy”in the 21st century.Compared with traditional high-pressure gaseous and cryogenic liquid hydrog...As one of the most promising new energy sources,hydrogen energy is expected to usher in a full-fledged“hydrogen economy”in the 21st century.Compared with traditional high-pressure gaseous and cryogenic liquid hydrogen storage methods,solid-state chemical hydrogen storage shows significant advantages in safety,high efficiency,and cost-effectiveness.Magnesium-based lightweight hydrogen storage materials have attracted widespread attention due to their high gravimetric hydrogen storage density(7.6%)and favorable reversibility.However,their sluggish reaction kinetics and stringent operating conditions(with H2 release temperatures exceeding 350°C and H2 absorption pressures above 4 MPa)pose major challenges for practical applications.Domestic and international researchers have conducted in-depth studies to address these issues,achieving substantial progress in the modification of magnesium-based hydrogen storage alloys.This paper systematically elaborates on major modification techniques such as alloying,nanostructuring,and catalytic material doping,providing a comprehensive analysis of the strengths and limitations of each approach.Furthermore,it offers prospects for the future development of magnesium-based hydrogen storage materials by integrating current theoretical and experimental research findings.展开更多
Development of high performance,flexible piezoelectric nanogenerators(PENGs)is critical for advancing self-powered sensing and microelectronic applications.In this study,a hydrogen-bond substitute strategy was employe...Development of high performance,flexible piezoelectric nanogenerators(PENGs)is critical for advancing self-powered sensing and microelectronic applications.In this study,a hydrogen-bond substitute strategy was employed to fabricate a multi-layer PENG based on a cellulose/polyvinylidene fluoride(PVDF)blend film matrix,incorporating multi-phase BCZT(0.1BaZr_(0.2)Ti_(0.8)O_(3)-0.9Ba_(0.7)Ca_(0.3)TiO_(3))ceramic fillers.Structural characterization via SEM and TEM revealed that an intricate hydrogen-bond network facilitated the uniform dispersion of ceramic fillers within the composite film’s sub-layers.In order to study the effect of filler distribution on piezoelectric performance,the single-and double-layer composite films with varying BCZT configurations were produced and evaluated.The results demonstrated that double-layer PENGs exhibit significantly enhanced electrical output compared to their single-layer counterparts,with the D-L_(3)H_(7) configuration achieving an open circuit voltage(V_(OC))of 23.13 V and a short circuit current(I_(SC))of 8.32μA.This enhancement is attributed to increased inter-layer interfaces,which effectively suppressed charge injection and migration,leading to improved charge density.Additionally,the presence of sharp tipped hexagonal tetragonal phase nanoparticles induced an electric field enhancement effect,further optimizing performance.展开更多
Cyclohexene is an important raw material in the production of nylon.Selective hydrogenation of benzene is a key method for preparing cyclohexene.However,the Ru catalysts used in current industrial processes still face...Cyclohexene is an important raw material in the production of nylon.Selective hydrogenation of benzene is a key method for preparing cyclohexene.However,the Ru catalysts used in current industrial processes still face challenges,including high metal usage,high process costs,and low cyclohexene yield.This study utilizes existing literature data combined with machine learning methods to analyze the factors influencing benzene conversion,cyclohexene selectivity,and yield in the benzene hydrogenation to cyclohexene reaction.It constructs predictive models based on XGBoost and Random Forest algorithms.After analysis,it was found that reaction time,Ru content,and space velocity are key factors influencing cyclohexene yield,selectivity,and benzene conversion.Shapley Additive Explanations(SHAP)analysis and feature importance analysis further revealed the contribution of each variable to the reaction outcomes.Additionally,we randomly generated one million variable combinations using the Dirichlet distribution to attempt to predict high-yield catalyst formulations.This paper provides new insights into the application of machine learning in heterogeneous catalysis and offers some reference for further research.展开更多
Ion-solvaing membranes(ISMs)have received extensive attention in recent years as a key component in electrochemical energy conversion and storage devices.This article provides an overview of structural composition,per...Ion-solvaing membranes(ISMs)have received extensive attention in recent years as a key component in electrochemical energy conversion and storage devices.This article provides an overview of structural composition,performance advan-tages,research progress,ion conduction mechanism and existing issues of ISMs,primarily classifying them according to the matrix structure.A detailed analysis of performance enhancement methods,key performance indicators of ISMs and performance influencing factors is also presented.The article contributes to further optimizing the design and application of ion-solvation membranes,providing theoretical support for the development of fields such as hydrogen production through electrolysis of water and electrochemical energy in the future.展开更多
Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon...Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies.展开更多
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
The Ni/SBA-15 catalysts were synthesized using the in situ method and the influence of crystallization temperature on nickel utilization efficiency-a critical factor in mesoporous material design-was systematically in...The Ni/SBA-15 catalysts were synthesized using the in situ method and the influence of crystallization temperature on nickel utilization efficiency-a critical factor in mesoporous material design-was systematically investigated.The structural characteristics and nickel anchoring capacity were analyzed using XRD,BET,FT-IR,H2-TPR,and ICP-OES.The results demonstrated that the crystallization temperature significantly affected the framework order of SBA-15 and the surface anchoring efficiency of Ni ions.The nickel utilization efficiency increased from 8.4%at 80℃ to 60.49%at 140℃,but then decreased to 47.25%at 160℃,indicating an optimal crystallization temperature window.This provides crucial guidance for tailoring high-performance metal-doped molecular sieves.The optimal catalyst exhibited excellent performance in the hydrogenation of 1,4-butynediol(BYD):the BYD conversion reached 97.25%with 88.99%selectivity of 1,4-butenediol(BED)within 5 h,and reached 99.73%with 87.34%selectivity of 1,4-butanediol(BDO)after 20 h reaction.These results revealed the critical role of crystallization temperature in metal utilization and provided theoretical support for designing highly active molecular sieve catalysts.展开更多
In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using at...In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using attenuated total reflectance Fourier-transform infrared spectroscopy(ATR-FTIR),the molecular configurations of surface carboxyl groups(COOH),free carboxyl(COOH_(f))and hydrogen-bonded carboxyl(COOH_(HB),were directly correlated with the polar component of surface energy(γ^(s,p)).By decomposing theγ^(s,p)values of the PAA thin films as a sum of the contributions of COOH_(f)and COOH_(H B),the intrinsic polar component of surface energy of COOH_(H B)(γ_(H B)^(s,p*))was quantified for the first time as 8.34 mN/m,significantly lower than that of COOH_(f)(γ_(f)^(s,p*)=34 mN/m).This result highlights that hydrogen bonding markedly reduces theγ^(s,p),providing a rational explanation for the relatively large water contact angle observed on PAA thin films.Furthermore,it establishes a thermodynamic basis for estimating the fraction of surface COOH_(H B)groups(f H B)from wettability measurements.Further extension of the model to carboxyl-terminated self-assembled monolayers(COOH-SAMs)revealed that surface COOH density(ΣCOOH)critically regulates wetting behavior:whenΣCOOH ranges from 4.30 to 5.25 nm^(-2),COOH groups predominantly exist in a free state and facilitate effective hydration layers,thereby promoting superhydrophilicity.Overall,this study not only establishes a unified thermodynamic framework linking surface COOH configurations to macroscopic wettability,but also validates its universality by extending it to COOH-SAMs systems,thereby providing a unified theoretical framework for the controllable design of hydrophilicity in various COOH-functionalized surfaces.展开更多
Discussions about the future of energy sources and environmental sustainability are becoming critical on a global scale.The energy sector plays a central role in the economy,as the availability and cost of energy infl...Discussions about the future of energy sources and environmental sustainability are becoming critical on a global scale.The energy sector plays a central role in the economy,as the availability and cost of energy influence the competitiveness of economies,while the level of energy consumption impacts the standard of living for individuals.This paper aims to examine environmental challenges and steps for a sustainable transition towards a hydrogen economy,focusing on its potential as an alternative to fossil fuels and the importance of developing the hydrogen paradigm.The research methodology is based on a combination of qualitative and quantitative methods,including an analysis of global and regional trends in the energy transition,the impact of various forms of hydrogen production(green,blue,gray hydrogen)on greenhouse gas emissions,and a comparison of existing policies and strategies in different countries transitioning to a sustainable hydrogen economy.Research results show that green hydrogen,produced via electrolysis using renewable energy sources,holds the greatest potential for reducing greenhouse gas emissions,while gray and blue hydrogen can serve as transitional options.The development of the hydrogen paradigm,rooted in innovative technologies,renewable energy sources,and international cooperation,is crucial for decarbonization and the creation of a sustainable global economy,despite challenges such as high costs and the need for global coordination.The hydrogen paradigm is becoming a cornerstone of these efforts,laying the foundation for a long-term,sustainable global economy.Currently,over 180 hydrogen transport projects,60 distribution projects,80 storage projects,30 terminal and port projects,and more than 220 hydrogen production projects are under development worldwide.The global momentum of the hydrogen transition helps mitigate climate change and build a sustainable future.展开更多
https://www.sciencedirect.com/journal/energy-and-buildings/vol/350/suppl/CV olume 350,1 January 2026[OA]( 1)Rooftop agrivoltaic powered onsite hydrogenp roduction for insulated gasochromic smart glazing and hydrogen v...https://www.sciencedirect.com/journal/energy-and-buildings/vol/350/suppl/CV olume 350,1 January 2026[OA]( 1)Rooftop agrivoltaic powered onsite hydrogenp roduction for insulated gasochromic smart glazing and hydrogen vehicles:A holistic approach to sustainabler esidential building by Shanza Neda Hussain,Aritra Ghosh,Article 116675 A bstract:The study focused on designing a sustainable buildingi nvolving rooftop agrivoltaics,advanced glazing technologies ando nsite hydrogen production for a residential property in Birmingham,UK where green hydrogen produced by harnessinge lectricity generated by agrivoltaics system on rooftop of the building is employed to change the transparency of vacuum gasochromic glazing and refuel hydrogen-powered fuel cell vehicle using storage hydrogen for a sustainable building approach.展开更多
Chiral benzylic amines are important motifs in medicines.A dicationic nickel complex of chiral diphosphine(R)-Ph-BPE promotes highly enantioselective reductive amination of aryl alkyl ketones with arylamines using iso...Chiral benzylic amines are important motifs in medicines.A dicationic nickel complex of chiral diphosphine(R)-Ph-BPE promotes highly enantioselective reductive amination of aryl alkyl ketones with arylamines using isopropanol as hydrogen source.The reaction is easily scaled up in a gram-scale synthesis using 1 mol% nickel catalyst and it is applied to an asymmetric synthesis of(S)-rivastigmine.Building on this success,we achieved rare examples of asymmetric hydrogen borrowing reactions with arylamines using an Earth-abundant 3d metal,nickel.展开更多
Aqueous hydrogen(H_(2))gas batteries with unmatched lifespan are ideal for grid-scale energy storage,yet their deployment remains limited by the lack of low-cost,efficient,and durable hydrogen electrodes.Here,we repor...Aqueous hydrogen(H_(2))gas batteries with unmatched lifespan are ideal for grid-scale energy storage,yet their deployment remains limited by the lack of low-cost,efficient,and durable hydrogen electrodes.Here,we report a high-throughput and durable gas diffusion electrode(GDE)based on a simply preparable carbon-coated nickel(Ni@C)catalyst and the design of H_(2) diffusion channels.By optimizing the carbon layer structure,a balance between the intrinsic activity and stability of the catalyst can be achieved.This Ni@C catalyst exhibits a hydrogen oxidation reaction(HOR)activity of 44 A g^(-1) as well as remarkable hydrogen evolution reaction(HER)performance.Experimental results and theoretical calculations confirm the electronic interaction between the carbon shell and Ni.In combination with a hydrophobic design,a robust and durable Ni@C-GDE has been fabricated.This electrode achieves a low HOR polarization of only 91 mV at 30 mA cm^(-2),outperforming Pt/C-GDE(154 mV),and operates stably over 4500cycles(3200 h)for HOR/HER reversing.Enabled by this electrode,a 10 Ah Ni-H_(2) battery with an energy density of 156.3 Wh kg^(-1) and cost of 62.2$kWh^(-1) is demonstrated.This work offers a viable strategy for practical and scalable hydrogen gas batteries.展开更多
This study investigates the influence of hydrogen concentration at grain boundaries on the sensitivity of polycrystalline iron to hydrogen embrittlement using molecular dynamics simulations.These simulations reveal th...This study investigates the influence of hydrogen concentration at grain boundaries on the sensitivity of polycrystalline iron to hydrogen embrittlement using molecular dynamics simulations.These simulations reveal the diffusion behavior of hydrogen atoms at grain boundaries and their consequential impact on the hydrogen embrittlement sensitivity of iron alloys.The findings indicate that as the hydrogen concentration increases,both the yield strength and ultimate tensile strength of Fe-H alloys exhibit a declining trend.Moreover,the capture of hydrogen atoms at the grain boundaries significantly influences the fracture toughness of the material and promotes the formation and propagation of cracks.This study provides a novel theoretical basis for understanding and predicting the hydrogen embrittlement behavior of iron-based materials in hydrogen-rich environments,offering valuable insights for the design and development of Fe alloys with enhanced resistance to hydrogen embrittlement.展开更多
CdS photocatalysts have broad application prospects in environmental purification,energy conversion,and organic synthesis.However,their practical use is often hindered by the rapid recombination of photo-generated ele...CdS photocatalysts have broad application prospects in environmental purification,energy conversion,and organic synthesis.However,their practical use is often hindered by the rapid recombination of photo-generated electron-hole pairs,which limits their efficiency on various reactions.Controlling morphological structures and crystal facets engineering are effective methods to enhance the photocatalytic performance of CdS.In this work,two different forms of CdS photocatalysts were synthesized by a hydrothermal method,namely nanoflower-shaped (CdS-NF) and nanorod-shaped (CdS-NR) for hydrogen peroxide (H_(2)O_(2)) production.The exposed crystal planes of CdS-NF are mainly (0 0 2) planes,while the accesible crystal planes of CdS-NR are notablly (1 0 1) planes.Notably,the photocatalytic hydrogen peroxide production yield of CdS-NR was high at 1225.13 μmol·h^(−1)·g^(−1),which is 1.78 times higher than the H_(2)O_(2) generation rate of CdS-NF.Moreover,through free radical capture experiments and DFT calculations,the reaction pathway was further explored.Both different configurations of cadmium sulfide based photocatalysts conform to the reaction mechanism of oxygen reduction as the main and water oxidation as the auxiliary.展开更多
Metal hydrides with high hydrogen density provide promising hydrogen storage paths for hydrogen transportation.However,the requirement of highly pure H_(2)for re-hydrogenation limits its wide application.Here,amorphou...Metal hydrides with high hydrogen density provide promising hydrogen storage paths for hydrogen transportation.However,the requirement of highly pure H_(2)for re-hydrogenation limits its wide application.Here,amorphous Al_(2)O_(3)shells(10 nm)were deposited on the surface of highly active hydrogen storage material particles(MgH_(2)-ZrTi)by atomic layer deposition to obtain MgH_(2)-ZrTi@Al_(2)O_(3),which have been demonstrated to be air stable with selective adsorption of H_(2)under a hydrogen atmosphere with different impurities(CH_(4),O_(2),N_(2),and CO_(2)).About 4.79 wt% H_(2)was adsorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)at 75℃under 10%CH_(4)+90%H_(2)atmosphere within 3 h with no kinetic or density decay after 5 cycles(~100%capacity retention).Furthermore,about 4 wt%of H_(2)was absorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)under 0.1%O_(2)+0.4%N_(2)+99.5%H_(2)and 0.1%CO_(2)+0.4%N_(2)+99.5%H_(2)atmospheres at 100℃within 0.5 h,respectively,demonstrating the selective hydrogen absorption of MgH_(2)-ZrTi@10nmAl_(2)O_(3)in both oxygen-containing and carbon dioxide-containing atmospheres hydrogen atmosphere.The absorption and desorption curves of MgH_(2)-ZrTi@10nmAl_(2)O_(3)with and without absorption in pure hydrogen and then in 21%O_(2)+79%N_(2)for 1 h were found to overlap,further confirming the successful shielding effect of Al_(2)O_(3)shells against O_(2)and N_(2).The MgH_(2)-ZrTi@10nmAl_(2)O_(3)has been demonstrated to be air stable and have excellent selective hydrogen absorption performance under the atmosphere with CH_(4),O_(2),N_(2),and CO_(2).展开更多
Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Her...Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Herein,a MOF derived multi-phase FeNi_(3)-S catalyst was specially designed for efficient hydrogen storage in MgH_(2).Experiments confirmed that the incorporation of FeNi_(3)-S into MgH_(2) significantly lowered the desorption temperature and accelerated the kinetics of hydrogen desorption and reabsorption.The initial dehydrogenation temperature of the MgH_(2)+10 wt% FeNi_(3)-S composite was 202 ℃,which was 123 ℃ lower than that of pure MgH_(2).At 325 ℃,the MgH_(2)+10 wt% FeNi_(3)-S composite released 6.57 wt% H_(2)(fully dehydrogenated) within 1000 s.Remarkably,MgH_(2)+ 10 wt% FeNi_(3)-S composite initiated rehydrogenation at room temperature and rapidly absorbed 2.49 wt% H_(2) within 30 min at 100 ℃.Moreover,6.3 wt% H_(2) was still retained after 20 cycles at 300 ℃,demonstrating the superior cycling performance of the MgH_(2)+10 wt% FeNi_(3)-S composite.The activation energy fitting calculations further evidenced the addition of FeNi_(3)-S enhanced the de/resorption kinetics of MgH_(2)(E_(a)= 98.6 k J/mol and 43.3 k J/mol,respectively).Through phase and microstructural analysis,it was determined that the exceptional hydrogen storage performance of the composite was attributed to the in-situ formation of Mg/Mg_(2)Ni + Fe/MgS and MgH_(2)/Mg_(2)NiH_(4)+Fe/MgS hydrogen storage systems.Further mechanistic analysis revealed that Mg_(2)Ni/Mg_(2)NiH_(4) served as “hydrogen pump” and Fe/Mg S served as “hydrogen diffusion channel”,thus accelerating the dissociation and recombination of hydrogen molecules.In conclusion,this work offers insight into catalysts combining transition metal alloys and transition metal sulfide for exerting muti-phase synergistic effect on boosting the dehydrogenation/hydrogenation reactions of MgH_(2),which can also inspire future pioneering work on designing and fabricating high efficient catalysts in other energy storage related areas.展开更多
Photocatalysis is one of the most promising technologies for solving environmental and energy problems,but current photocatalysts still suffer from low visible light utilization and insufficient photogenerated charge ...Photocatalysis is one of the most promising technologies for solving environmental and energy problems,but current photocatalysts still suffer from low visible light utilization and insufficient photogenerated charge separation efficiency.Therefore,in this work,D-A tubular materials with tubular carbon nitride(TCN)as electron donor(D)and 2-mercaptobenzothiazole(BZ)as electron acceptor(A)were constructed by molecular doping and modulation of the carbon nitride geometry.It was shown that the introduction of BZ could modulate the electronic structure of the catalyst,promote electron migration from TCN to BZ,and inhibit the recombination of photogenerated electrons and holes.Meanwhile,the ultra-thin tubular structure could expose more active sites.In addition,the adsorption of protons by BZ-TCN was further improved due to the modulation of the charge distribution between the components by the introduction of small molecules.Among them,the photocatalytic hydrogen production rate of BZ_(0.1)-TCN was twice that of TCN.The in-depth discussion of the components through theoretical calculations and characterization tests contributes to the understanding of the mechanism of photocatalytic hydrogen production.展开更多
Electrochemical nitrate reduction reaction(NO_(3)RR)is a sustainable strategy to treat wastewater and produce ammonia.However,it is still a challenge to prepare electrocatalysts with high activity and selectivity.Here...Electrochemical nitrate reduction reaction(NO_(3)RR)is a sustainable strategy to treat wastewater and produce ammonia.However,it is still a challenge to prepare electrocatalysts with high activity and selectivity.Herein,the CuO_(x) nanowires supported Ru nanoclusters(Ru-CuO_(x))were fabricated via a three-step procedure for efficient nitrate conversion and highly selective ammonia generation.The prepared RuCuO_(x) shows a high ammonia yield rate of 2286.5μg h^(-1) cm^(-2) at-0.7 V vs.RHE and Faradaic efficiency(FE)of 80.1%at-0.4 V vs.RHE.Additionally,the nitrate conversion rate exceeds 90%at the potential range from-0.2 to-0.7 V vs.RHE,and the ammonia selectivity can reach 97.7%at-0.7 V vs.RHE in100 mg L^(-1) NaNO_(3) solution.The systematic characterizations clarify that the introduction of Ru not only regulates the electronic structure of CuO_(x) and accelerates the reconstruction of CuO_(x) to Cu but also promotes H2O dissociation to generate active hydrogen.Moreover.in-situ Raman spectroscopy reveals that the formed Ru-Cu is considered the actual active species during the NO_(3)RR.Density functional theory(DFT)calculations further prove that the obtained Ru-Cu facilitates the adsorption of nitrate and lowers the Gibbs free energy of the rate-determining step,thus improving the NO_(3)RR performance.展开更多
基金supported by the National Natural Science Foundation of China(22138009)the Fundamental Research Funds for the Central Universities of China。
文摘The preparation and application of supported gold and copper catalysts are fundamentally and practically very important.Herein,we confirm that the Au-Cu promoted In_(2)O_(3) catalyst demonstrates a significant electronic metal-support interaction(EMSI),which plays a critical role in CO_(2) hydrogenation to methanol and leads to significantly improved activity,compared to the mono-metallic Au and Cu promoted In_(2)O_(3)catalysts.This interaction arises from electron transfer between the oxygen deficient In_(2)O_(3) support and the bimetallic clusters,rendering both Au and Cu clusters positively charged.The presence of Cu^(3+)stabilizes and optimizes the content of oxygen vacancies,leading to a more pronounced positive charge on Au clusters(Au^(3+)).The ability to activate H_(2) is thus enhanced.CO adsorption on Au-Cu/In_(2)O_(3) is also stronger than Au/In_(2)O_(3).This results in higher methanol selectivity of Au-Cu/In_(2)O_(3),with which CO hydrogenation pathway is taken for CO_(2) hydrogenation to methanol.The enhanced H_(2) activation and stronger CO adsorption over Au-Cu/In_(2)O_(3) are key factors in boosting the activity for methanol formation from CO_(2)hvdrogenation.
基金Supported by National Key R&D Program of China(2022YFA1503400)。
文摘Aiming at the problems of insufficient activity and selectivity of Cu-based catalysts in CO_(2)hydrogenation to methanol,Al_(2)O_(3),ZrO_(2)and CeO_(2)modified Cu-ZnO catalysts by the co-precipitation method were prepared,and the influence mechanism of additives on the structure-performance relationship of the catalysts was systematically explored.Through a variety of characterization methods such as XRD,N2 physical adsorption-desorption,TEM,H_(2)-TPR,CO_(2)-TPD and XPS,combined with catalytic performance evaluation experiments,the correlation between the microstructure of catalysts and the reaction performance of CO_(2)hydrogenation to methanol was analyzed in depth.The results show that metal additives significantly improve the performance of catalysts.After the introduction of additives,the specific surface area and pore volume of the catalysts increase,the grain size of Cu decreases,and its dispersion improves.The Ce-modified CZC catalyst exhibited the best performance,with the grain size of CuO as small as 11.41 nm,and the surface oxygen vacancy concentration(OⅡ/OⅠ=3.15)was significantly higher than that of other samples.The reaction performance test shows that under the conditions of 2.8 MPa,8000 h−1 and 280℃,the CO_(2)conversion of the CZC catalyst reached 18.83%,the methanol selectivity was 68.40%,and the methanol yield was 12.88%,all of which are superior to other catalysts.Its excellent performance can be attributed to the fact that CeO_(2)enhances the metal-support interaction,increases the surface basicity,promotes the adsorption and activation of CO_(2),and simultaneously inhibits the reverse water-gas shift side reaction.This study clarifies the structure-activity regulation mechanism of additive modification on Cu-ZnO catalysts,providing a theoretical basis and technical reference for the development of efficient catalysts for CO_(2)hydrogenation to methanol.
基金Supported by Design and Performance Study of High-flux Metal Hydride Reactor Based on the Bionic Optimization(2078262)the‘Four-Chain’Integration Project at the Qinchuangyuan Chief Platform(S2025-YF-ZDXM)。
文摘As one of the most promising new energy sources,hydrogen energy is expected to usher in a full-fledged“hydrogen economy”in the 21st century.Compared with traditional high-pressure gaseous and cryogenic liquid hydrogen storage methods,solid-state chemical hydrogen storage shows significant advantages in safety,high efficiency,and cost-effectiveness.Magnesium-based lightweight hydrogen storage materials have attracted widespread attention due to their high gravimetric hydrogen storage density(7.6%)and favorable reversibility.However,their sluggish reaction kinetics and stringent operating conditions(with H2 release temperatures exceeding 350°C and H2 absorption pressures above 4 MPa)pose major challenges for practical applications.Domestic and international researchers have conducted in-depth studies to address these issues,achieving substantial progress in the modification of magnesium-based hydrogen storage alloys.This paper systematically elaborates on major modification techniques such as alloying,nanostructuring,and catalytic material doping,providing a comprehensive analysis of the strengths and limitations of each approach.Furthermore,it offers prospects for the future development of magnesium-based hydrogen storage materials by integrating current theoretical and experimental research findings.
基金National Natural Science Foundation of China(52472132)Opening Project of Engineering Research Center of Eco-friendly Polymeric Materials,Ministry of Education(EFP-KF2403)Innovation Service Capability Support Plan of Xianyang(Science and Technology Innovation Talents)。
文摘Development of high performance,flexible piezoelectric nanogenerators(PENGs)is critical for advancing self-powered sensing and microelectronic applications.In this study,a hydrogen-bond substitute strategy was employed to fabricate a multi-layer PENG based on a cellulose/polyvinylidene fluoride(PVDF)blend film matrix,incorporating multi-phase BCZT(0.1BaZr_(0.2)Ti_(0.8)O_(3)-0.9Ba_(0.7)Ca_(0.3)TiO_(3))ceramic fillers.Structural characterization via SEM and TEM revealed that an intricate hydrogen-bond network facilitated the uniform dispersion of ceramic fillers within the composite film’s sub-layers.In order to study the effect of filler distribution on piezoelectric performance,the single-and double-layer composite films with varying BCZT configurations were produced and evaluated.The results demonstrated that double-layer PENGs exhibit significantly enhanced electrical output compared to their single-layer counterparts,with the D-L_(3)H_(7) configuration achieving an open circuit voltage(V_(OC))of 23.13 V and a short circuit current(I_(SC))of 8.32μA.This enhancement is attributed to increased inter-layer interfaces,which effectively suppressed charge injection and migration,leading to improved charge density.Additionally,the presence of sharp tipped hexagonal tetragonal phase nanoparticles induced an electric field enhancement effect,further optimizing performance.
基金Supported by CAS Basic and Interdisciplinary Frontier Scientific Research Pilot Project(XDB1190300,XDB1190302)Youth Innovation Promotion Association CAS(Y2021056)+1 种基金Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy(YLU-DNL Fund 2022007)The special fund for Science and Technology Innovation Teams of Shanxi Province(202304051001007)。
文摘Cyclohexene is an important raw material in the production of nylon.Selective hydrogenation of benzene is a key method for preparing cyclohexene.However,the Ru catalysts used in current industrial processes still face challenges,including high metal usage,high process costs,and low cyclohexene yield.This study utilizes existing literature data combined with machine learning methods to analyze the factors influencing benzene conversion,cyclohexene selectivity,and yield in the benzene hydrogenation to cyclohexene reaction.It constructs predictive models based on XGBoost and Random Forest algorithms.After analysis,it was found that reaction time,Ru content,and space velocity are key factors influencing cyclohexene yield,selectivity,and benzene conversion.Shapley Additive Explanations(SHAP)analysis and feature importance analysis further revealed the contribution of each variable to the reaction outcomes.Additionally,we randomly generated one million variable combinations using the Dirichlet distribution to attempt to predict high-yield catalyst formulations.This paper provides new insights into the application of machine learning in heterogeneous catalysis and offers some reference for further research.
基金supported by the National Key Research and Development Program of China (2022YFE0138900)the “Scientific and Technical Innovation Action Plan” Basic Research Field of Shanghai Science and Technology Committee (19JC1410500)。
文摘Ion-solvaing membranes(ISMs)have received extensive attention in recent years as a key component in electrochemical energy conversion and storage devices.This article provides an overview of structural composition,performance advan-tages,research progress,ion conduction mechanism and existing issues of ISMs,primarily classifying them according to the matrix structure.A detailed analysis of performance enhancement methods,key performance indicators of ISMs and performance influencing factors is also presented.The article contributes to further optimizing the design and application of ion-solvation membranes,providing theoretical support for the development of fields such as hydrogen production through electrolysis of water and electrochemical energy in the future.
基金Supported by the National Key Research and Development Program of China(2023YFB4104500,2023YFB4104502)the National Natural Science Foundation of China(22138013)the Taishan Scholar Project(ts201712020).
文摘Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies.
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.
文摘The Ni/SBA-15 catalysts were synthesized using the in situ method and the influence of crystallization temperature on nickel utilization efficiency-a critical factor in mesoporous material design-was systematically investigated.The structural characteristics and nickel anchoring capacity were analyzed using XRD,BET,FT-IR,H2-TPR,and ICP-OES.The results demonstrated that the crystallization temperature significantly affected the framework order of SBA-15 and the surface anchoring efficiency of Ni ions.The nickel utilization efficiency increased from 8.4%at 80℃ to 60.49%at 140℃,but then decreased to 47.25%at 160℃,indicating an optimal crystallization temperature window.This provides crucial guidance for tailoring high-performance metal-doped molecular sieves.The optimal catalyst exhibited excellent performance in the hydrogenation of 1,4-butynediol(BYD):the BYD conversion reached 97.25%with 88.99%selectivity of 1,4-butenediol(BED)within 5 h,and reached 99.73%with 87.34%selectivity of 1,4-butanediol(BDO)after 20 h reaction.These results revealed the critical role of crystallization temperature in metal utilization and provided theoretical support for designing highly active molecular sieve catalysts.
文摘In this study,polyacrylic acid(PAA)films were employed as a model system,and a series of PAA films with tunable water wettability was systematically prepared by varying molecular weight and curing temperature.Using attenuated total reflectance Fourier-transform infrared spectroscopy(ATR-FTIR),the molecular configurations of surface carboxyl groups(COOH),free carboxyl(COOH_(f))and hydrogen-bonded carboxyl(COOH_(HB),were directly correlated with the polar component of surface energy(γ^(s,p)).By decomposing theγ^(s,p)values of the PAA thin films as a sum of the contributions of COOH_(f)and COOH_(H B),the intrinsic polar component of surface energy of COOH_(H B)(γ_(H B)^(s,p*))was quantified for the first time as 8.34 mN/m,significantly lower than that of COOH_(f)(γ_(f)^(s,p*)=34 mN/m).This result highlights that hydrogen bonding markedly reduces theγ^(s,p),providing a rational explanation for the relatively large water contact angle observed on PAA thin films.Furthermore,it establishes a thermodynamic basis for estimating the fraction of surface COOH_(H B)groups(f H B)from wettability measurements.Further extension of the model to carboxyl-terminated self-assembled monolayers(COOH-SAMs)revealed that surface COOH density(ΣCOOH)critically regulates wetting behavior:whenΣCOOH ranges from 4.30 to 5.25 nm^(-2),COOH groups predominantly exist in a free state and facilitate effective hydration layers,thereby promoting superhydrophilicity.Overall,this study not only establishes a unified thermodynamic framework linking surface COOH configurations to macroscopic wettability,but also validates its universality by extending it to COOH-SAMs systems,thereby providing a unified theoretical framework for the controllable design of hydrophilicity in various COOH-functionalized surfaces.
文摘Discussions about the future of energy sources and environmental sustainability are becoming critical on a global scale.The energy sector plays a central role in the economy,as the availability and cost of energy influence the competitiveness of economies,while the level of energy consumption impacts the standard of living for individuals.This paper aims to examine environmental challenges and steps for a sustainable transition towards a hydrogen economy,focusing on its potential as an alternative to fossil fuels and the importance of developing the hydrogen paradigm.The research methodology is based on a combination of qualitative and quantitative methods,including an analysis of global and regional trends in the energy transition,the impact of various forms of hydrogen production(green,blue,gray hydrogen)on greenhouse gas emissions,and a comparison of existing policies and strategies in different countries transitioning to a sustainable hydrogen economy.Research results show that green hydrogen,produced via electrolysis using renewable energy sources,holds the greatest potential for reducing greenhouse gas emissions,while gray and blue hydrogen can serve as transitional options.The development of the hydrogen paradigm,rooted in innovative technologies,renewable energy sources,and international cooperation,is crucial for decarbonization and the creation of a sustainable global economy,despite challenges such as high costs and the need for global coordination.The hydrogen paradigm is becoming a cornerstone of these efforts,laying the foundation for a long-term,sustainable global economy.Currently,over 180 hydrogen transport projects,60 distribution projects,80 storage projects,30 terminal and port projects,and more than 220 hydrogen production projects are under development worldwide.The global momentum of the hydrogen transition helps mitigate climate change and build a sustainable future.
文摘https://www.sciencedirect.com/journal/energy-and-buildings/vol/350/suppl/CV olume 350,1 January 2026[OA]( 1)Rooftop agrivoltaic powered onsite hydrogenp roduction for insulated gasochromic smart glazing and hydrogen vehicles:A holistic approach to sustainabler esidential building by Shanza Neda Hussain,Aritra Ghosh,Article 116675 A bstract:The study focused on designing a sustainable buildingi nvolving rooftop agrivoltaics,advanced glazing technologies ando nsite hydrogen production for a residential property in Birmingham,UK where green hydrogen produced by harnessinge lectricity generated by agrivoltaics system on rooftop of the building is employed to change the transparency of vacuum gasochromic glazing and refuel hydrogen-powered fuel cell vehicle using storage hydrogen for a sustainable building approach.
基金supported by the National Natural Science Foundation of China(Nos.22271007,W2431014)Peking University Shenzhen Graduate School+2 种基金State Key Laboratory of Chemical OncogenomicsShenzhen Key Laboratory of Chemical GenomicsShenzhen Bay Laboratory.
文摘Chiral benzylic amines are important motifs in medicines.A dicationic nickel complex of chiral diphosphine(R)-Ph-BPE promotes highly enantioselective reductive amination of aryl alkyl ketones with arylamines using isopropanol as hydrogen source.The reaction is easily scaled up in a gram-scale synthesis using 1 mol% nickel catalyst and it is applied to an asymmetric synthesis of(S)-rivastigmine.Building on this success,we achieved rare examples of asymmetric hydrogen borrowing reactions with arylamines using an Earth-abundant 3d metal,nickel.
基金financially supported by the“National Natural Science Foundation of China”(No.22279082)the“Natural Science Foundation of Sichuan”(2025YFHZ0056)。
文摘Aqueous hydrogen(H_(2))gas batteries with unmatched lifespan are ideal for grid-scale energy storage,yet their deployment remains limited by the lack of low-cost,efficient,and durable hydrogen electrodes.Here,we report a high-throughput and durable gas diffusion electrode(GDE)based on a simply preparable carbon-coated nickel(Ni@C)catalyst and the design of H_(2) diffusion channels.By optimizing the carbon layer structure,a balance between the intrinsic activity and stability of the catalyst can be achieved.This Ni@C catalyst exhibits a hydrogen oxidation reaction(HOR)activity of 44 A g^(-1) as well as remarkable hydrogen evolution reaction(HER)performance.Experimental results and theoretical calculations confirm the electronic interaction between the carbon shell and Ni.In combination with a hydrophobic design,a robust and durable Ni@C-GDE has been fabricated.This electrode achieves a low HOR polarization of only 91 mV at 30 mA cm^(-2),outperforming Pt/C-GDE(154 mV),and operates stably over 4500cycles(3200 h)for HOR/HER reversing.Enabled by this electrode,a 10 Ah Ni-H_(2) battery with an energy density of 156.3 Wh kg^(-1) and cost of 62.2$kWh^(-1) is demonstrated.This work offers a viable strategy for practical and scalable hydrogen gas batteries.
基金supported by the National Science Fund for Distinguished Young Scholars(No.52425404).
文摘This study investigates the influence of hydrogen concentration at grain boundaries on the sensitivity of polycrystalline iron to hydrogen embrittlement using molecular dynamics simulations.These simulations reveal the diffusion behavior of hydrogen atoms at grain boundaries and their consequential impact on the hydrogen embrittlement sensitivity of iron alloys.The findings indicate that as the hydrogen concentration increases,both the yield strength and ultimate tensile strength of Fe-H alloys exhibit a declining trend.Moreover,the capture of hydrogen atoms at the grain boundaries significantly influences the fracture toughness of the material and promotes the formation and propagation of cracks.This study provides a novel theoretical basis for understanding and predicting the hydrogen embrittlement behavior of iron-based materials in hydrogen-rich environments,offering valuable insights for the design and development of Fe alloys with enhanced resistance to hydrogen embrittlement.
基金support from Natural Science Foundation of Shandong Province(ZR2022MB049,ZR2021MB104)the National Natural Science Foundation of China(22078174).
文摘CdS photocatalysts have broad application prospects in environmental purification,energy conversion,and organic synthesis.However,their practical use is often hindered by the rapid recombination of photo-generated electron-hole pairs,which limits their efficiency on various reactions.Controlling morphological structures and crystal facets engineering are effective methods to enhance the photocatalytic performance of CdS.In this work,two different forms of CdS photocatalysts were synthesized by a hydrothermal method,namely nanoflower-shaped (CdS-NF) and nanorod-shaped (CdS-NR) for hydrogen peroxide (H_(2)O_(2)) production.The exposed crystal planes of CdS-NF are mainly (0 0 2) planes,while the accesible crystal planes of CdS-NR are notablly (1 0 1) planes.Notably,the photocatalytic hydrogen peroxide production yield of CdS-NR was high at 1225.13 μmol·h^(−1)·g^(−1),which is 1.78 times higher than the H_(2)O_(2) generation rate of CdS-NF.Moreover,through free radical capture experiments and DFT calculations,the reaction pathway was further explored.Both different configurations of cadmium sulfide based photocatalysts conform to the reaction mechanism of oxygen reduction as the main and water oxidation as the auxiliary.
基金supported by the National Natural Science Foundation of China(22175136)the State Key Laboratory of Electrical Insulation and Power Equipment(EIPE23127)the Fundamental Research Funds for the Central Universities(xtr052024009).
文摘Metal hydrides with high hydrogen density provide promising hydrogen storage paths for hydrogen transportation.However,the requirement of highly pure H_(2)for re-hydrogenation limits its wide application.Here,amorphous Al_(2)O_(3)shells(10 nm)were deposited on the surface of highly active hydrogen storage material particles(MgH_(2)-ZrTi)by atomic layer deposition to obtain MgH_(2)-ZrTi@Al_(2)O_(3),which have been demonstrated to be air stable with selective adsorption of H_(2)under a hydrogen atmosphere with different impurities(CH_(4),O_(2),N_(2),and CO_(2)).About 4.79 wt% H_(2)was adsorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)at 75℃under 10%CH_(4)+90%H_(2)atmosphere within 3 h with no kinetic or density decay after 5 cycles(~100%capacity retention).Furthermore,about 4 wt%of H_(2)was absorbed by MgH_(2)-ZrTi@10nmAl_(2)O_(3)under 0.1%O_(2)+0.4%N_(2)+99.5%H_(2)and 0.1%CO_(2)+0.4%N_(2)+99.5%H_(2)atmospheres at 100℃within 0.5 h,respectively,demonstrating the selective hydrogen absorption of MgH_(2)-ZrTi@10nmAl_(2)O_(3)in both oxygen-containing and carbon dioxide-containing atmospheres hydrogen atmosphere.The absorption and desorption curves of MgH_(2)-ZrTi@10nmAl_(2)O_(3)with and without absorption in pure hydrogen and then in 21%O_(2)+79%N_(2)for 1 h were found to overlap,further confirming the successful shielding effect of Al_(2)O_(3)shells against O_(2)and N_(2).The MgH_(2)-ZrTi@10nmAl_(2)O_(3)has been demonstrated to be air stable and have excellent selective hydrogen absorption performance under the atmosphere with CH_(4),O_(2),N_(2),and CO_(2).
基金supported by the National Key R&D Program of China (No.2022YFB3803703)the National Natural Science Foundation of China (Nos.52071141,52271212,52201250,51771056,22305104)+1 种基金the Natural Science Foundation of Jiangsu Province (No.BK20210893)the Ministry of Science and Technology of the People’s Republic of China (No.G2023014022L)。
文摘Magnesium hydride(MgH_(2)) demonstrates immense potential as a solid-state hydrogen storage material,while its commercial utilization is impeded by the elevated operating temperature and sluggish reaction kinetics.Herein,a MOF derived multi-phase FeNi_(3)-S catalyst was specially designed for efficient hydrogen storage in MgH_(2).Experiments confirmed that the incorporation of FeNi_(3)-S into MgH_(2) significantly lowered the desorption temperature and accelerated the kinetics of hydrogen desorption and reabsorption.The initial dehydrogenation temperature of the MgH_(2)+10 wt% FeNi_(3)-S composite was 202 ℃,which was 123 ℃ lower than that of pure MgH_(2).At 325 ℃,the MgH_(2)+10 wt% FeNi_(3)-S composite released 6.57 wt% H_(2)(fully dehydrogenated) within 1000 s.Remarkably,MgH_(2)+ 10 wt% FeNi_(3)-S composite initiated rehydrogenation at room temperature and rapidly absorbed 2.49 wt% H_(2) within 30 min at 100 ℃.Moreover,6.3 wt% H_(2) was still retained after 20 cycles at 300 ℃,demonstrating the superior cycling performance of the MgH_(2)+10 wt% FeNi_(3)-S composite.The activation energy fitting calculations further evidenced the addition of FeNi_(3)-S enhanced the de/resorption kinetics of MgH_(2)(E_(a)= 98.6 k J/mol and 43.3 k J/mol,respectively).Through phase and microstructural analysis,it was determined that the exceptional hydrogen storage performance of the composite was attributed to the in-situ formation of Mg/Mg_(2)Ni + Fe/MgS and MgH_(2)/Mg_(2)NiH_(4)+Fe/MgS hydrogen storage systems.Further mechanistic analysis revealed that Mg_(2)Ni/Mg_(2)NiH_(4) served as “hydrogen pump” and Fe/Mg S served as “hydrogen diffusion channel”,thus accelerating the dissociation and recombination of hydrogen molecules.In conclusion,this work offers insight into catalysts combining transition metal alloys and transition metal sulfide for exerting muti-phase synergistic effect on boosting the dehydrogenation/hydrogenation reactions of MgH_(2),which can also inspire future pioneering work on designing and fabricating high efficient catalysts in other energy storage related areas.
基金financially supported by the National Natural Science Foundation of China(No.22208129)2023 Jiangsu Province Large Scientific Instrument Open Sharing Autonomous Research Project(No.TC2023A033)。
文摘Photocatalysis is one of the most promising technologies for solving environmental and energy problems,but current photocatalysts still suffer from low visible light utilization and insufficient photogenerated charge separation efficiency.Therefore,in this work,D-A tubular materials with tubular carbon nitride(TCN)as electron donor(D)and 2-mercaptobenzothiazole(BZ)as electron acceptor(A)were constructed by molecular doping and modulation of the carbon nitride geometry.It was shown that the introduction of BZ could modulate the electronic structure of the catalyst,promote electron migration from TCN to BZ,and inhibit the recombination of photogenerated electrons and holes.Meanwhile,the ultra-thin tubular structure could expose more active sites.In addition,the adsorption of protons by BZ-TCN was further improved due to the modulation of the charge distribution between the components by the introduction of small molecules.Among them,the photocatalytic hydrogen production rate of BZ_(0.1)-TCN was twice that of TCN.The in-depth discussion of the components through theoretical calculations and characterization tests contributes to the understanding of the mechanism of photocatalytic hydrogen production.
基金the Natural Science Foundation of China(Grant No.NSFC-22072062,22202098)the Science and Technology Project of China Northern Rare Earth(BFXT-2023-D-0048 and BFXT-2022-D-0078)。
文摘Electrochemical nitrate reduction reaction(NO_(3)RR)is a sustainable strategy to treat wastewater and produce ammonia.However,it is still a challenge to prepare electrocatalysts with high activity and selectivity.Herein,the CuO_(x) nanowires supported Ru nanoclusters(Ru-CuO_(x))were fabricated via a three-step procedure for efficient nitrate conversion and highly selective ammonia generation.The prepared RuCuO_(x) shows a high ammonia yield rate of 2286.5μg h^(-1) cm^(-2) at-0.7 V vs.RHE and Faradaic efficiency(FE)of 80.1%at-0.4 V vs.RHE.Additionally,the nitrate conversion rate exceeds 90%at the potential range from-0.2 to-0.7 V vs.RHE,and the ammonia selectivity can reach 97.7%at-0.7 V vs.RHE in100 mg L^(-1) NaNO_(3) solution.The systematic characterizations clarify that the introduction of Ru not only regulates the electronic structure of CuO_(x) and accelerates the reconstruction of CuO_(x) to Cu but also promotes H2O dissociation to generate active hydrogen.Moreover.in-situ Raman spectroscopy reveals that the formed Ru-Cu is considered the actual active species during the NO_(3)RR.Density functional theory(DFT)calculations further prove that the obtained Ru-Cu facilitates the adsorption of nitrate and lowers the Gibbs free energy of the rate-determining step,thus improving the NO_(3)RR performance.
