A comprehensive understanding of the structure and dynamic evolution of catalytic active sites is vital for advancing the study of liquid-phase acetylene hydrochlorination.Here,we successfully developed a Ru-DIPEA/TMS...A comprehensive understanding of the structure and dynamic evolution of catalytic active sites is vital for advancing the study of liquid-phase acetylene hydrochlorination.Here,we successfully developed a Ru-DIPEA/TMS catalyst optimised through systematic composition and condition tuning,demonstrating exceptional performance with 95.5%C_(2)H_(2)conversion and sustaining over 91.1%activity along with nearly 100%selectivity for VCM during a continuous 900-h test.Using a combination of characterisation techniques,including UV–vis spectroscopy,FT-IR spectroscopy,X-ray photoelectron spectroscopy,singlecrystal X-ray diffraction,and X-ray absorption spectroscopy,along with density functional theory(DFT)calculations,the structure and dynamic behaviour of the active sites were thoroughly investigated under the synergistic influence of ligands and HCl.The results revealed that HCl activation induces a significant structural transformation of the active sites,leading to the formation of a hexacoordinate complex,Ru(CO)_(2)C_(12)(C_(6)H_(15)N·HCl)_(2).DFT calculations further elucidated the mechanism underlying active site formation,revealing that an increased electron density around the Ru centre and corresponding changes in its coordination environment play critical roles in enhancing catalyst stability and activity.This study contributes to a deeper understanding of the structural basis of active site evolution during acetylene hydrochlorination,offering both practical insights into industrial applications and foundational knowledge for advancing liquid-phase catalysis.展开更多
Oxygen evolution reaction(OER)is a kinetically harsh four-electron anode reaction that requires a large overpotential to provide current and is of great importance in renewable electrochemical technique.Ir/Rubased per...Oxygen evolution reaction(OER)is a kinetically harsh four-electron anode reaction that requires a large overpotential to provide current and is of great importance in renewable electrochemical technique.Ir/Rubased perovskite oxides hold great significance for application as OER electrocatalysts,due to that their multimetal-oxide forms can reduce the use of noble metals,and their compositional tunability can modulate the electronic structure and optimize OER performance.However,high operating potentials and corrosive environments pose a serious challenge to the development of durable Ir-based and Ru-based perovskite electrocatalysts.Tremendous efforts have been dedicated to improving the Ir/Ru-based perovskite activity to enhance the efficiency;however,progress in improving the durability of Ir/Ru-based perovskite electrocatalysts has been rather limited.In this review,the recent research progress of Ir/Ru-based perovskites is reviewed from the perspective of heteroatom doping,structural modulation,and formation of heterostructures.The dissolution mechanism studies of Ir/Ru and experimental attempts to improve the durability of Ir/Ru-based perovskite electrocatalysts are discussed.Challenges and outlooks for further developing Ru-and Irbased perovskite oxygen electrocatalysts are also presented.展开更多
Series of carbon nanotube supported Ru-based catalysts were prepared by impregnation method and applied successfully for complete removal of CO by CO selective methanation from H2-rich gas stream conducted in a fixed-...Series of carbon nanotube supported Ru-based catalysts were prepared by impregnation method and applied successfully for complete removal of CO by CO selective methanation from H2-rich gas stream conducted in a fixed-bed quartz tubular reactor at ambient pressure. It was found that the metal promoter, reduction temperature and metal loading affected the catalytic properties significantly. The most excellent performance was presented by 30 wt% Ru-Zr/CNTs catalyst reduced at 350 ℃. Since it decreased CO concentration to below 10 ppm from 12000 ppm by CO selective methanation at the temperature range of 180-240 ℃, and kept CO selectivity higher than 85% at the temperature below 200 ℃. Characterization using XRD, TEM, H2-TPR and XPS suggests that Zr modification of Ru/CNTs results in the weakening of the interaction between Ru and CNTs, a higher Ru dispersion and the oxidization of surface Ru. Amorphous and high dispersed Ru particles with small size were obtained for 30 wt% Ru-Zr/CNTs catalyst reduced at 350 ℃, leading to excellent catalytic performance in CO selective methanation.展开更多
Water electrolysis using proton-exchange membranes is one of the most promising technologies for carbon-neutral and sustainable energy production.Generally,the overall efficiency of water splitting is limited by the o...Water electrolysis using proton-exchange membranes is one of the most promising technologies for carbon-neutral and sustainable energy production.Generally,the overall efficiency of water splitting is limited by the oxygen evolution reaction(OER).Nevertheless,a trade-off between activity and stability exists for most electrocatalytic materials in strong acids and oxidizing media,and the development of efficient and stable catalytic materials has been an important focus of research.In this view,gaining in-depth insights into the OER system,particularly the interactions between reaction intermediates and active sites,is significantly important.To this end,this review introduces the fundamentals of the OER over Ru-based materials,including the conventional adsorbate evolution mechanism,lattice oxygen oxidation mechanism,and oxide path mechanism.Moreover,the up-to-date progress of representative modifications for improving OER performance is further discussed with reference to specific mechanisms,such as tuning of geometric,electronic structures,incorporation of proton acceptors,and optimization of metal-oxygen covalency.Finally,some valuable insights into the challenges and opportunities for OER electrocatalysts are provided with the aim to promote the development of next-generation catalysts with high activity and excellent stability.展开更多
The fundamental insights of the reaction mechanism,especially the synergistic effect between oxygen vacancies and basic sites,are highly promising yet challenging for Ru-based catalysts during carbon dioxide(CO_(2))me...The fundamental insights of the reaction mechanism,especially the synergistic effect between oxygen vacancies and basic sites,are highly promising yet challenging for Ru-based catalysts during carbon dioxide(CO_(2))methanation.Herein,a series of Rubased catalysts were employed to study the mechanism of CO_(2) methanation.It is found that Ru/CeO_(2) catalyst exhibits a much higher CO_(2) conversion(86%)and CH4 selectivity(100%),as well as excellent stability of 30 h due to the existence of abundant oxygen vacancies and weak basic sites.Additionally,the in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and density functional theory(DFT)calculations reveal that the formate formation step dominated the hydrogenation route on Ru/CeO_(2) catalyst,and the b-HCOO^(*)could be the key intermediate due to b-HCOO^(*)is more easily hydrogenated to methane than m-HCOO^(*).The systematic study marks the significance of precise tailoring of the synergistic relationship between oxygen vacancies and basic sites for achieving the desired performance in CO_(2) methanation.展开更多
Green hydrogen energy developed through electrochemistry is one of the solutions to current energy problems.The less noble metal ruthenium(Ru)plays an important role in alkaline electrocatalytic hydrogen evolution rea...Green hydrogen energy developed through electrochemistry is one of the solutions to current energy problems.The less noble metal ruthenium(Ru)plays an important role in alkaline electrocatalytic hydrogen evolution reaction(HER)as an effective electrocatalyst.Nevertheless,the high cost(>110 RMB per gram)hinders the large-scale application of Ru in industrial hydrogen production.Moreover,the strong adsorption of OH*in-termediates over Ru limits the electrocatalytic performance in alkaline HER.Here,we report the Mo-doped Ru nanocluster embedded on N-doped carbon framework(RuMo/NC)as alkaline HER catalyst,which shows excellent catalytic performance with an overpotential of 24.2 mV to reach 10 mA cm-2 with only 0.4 wt%o of Ru,much lower than that of most reported Ru-based catalysts.DFT calculations reveal the introduction of Mo has improved the activity by alleviating the poisoning effect of OH*over Ru in HER.Through fully utilizing Ru in the catalyst,this work marks a step forward in the development of Ru-based catalysts in alkaline HER.展开更多
Hydrogen has emerged as a promising environmentally friendly energy source. The development of lowcost, highly active, stable, and easily synthesized catalysts for hydrogen evolution reactions(HER) remains a significa...Hydrogen has emerged as a promising environmentally friendly energy source. The development of lowcost, highly active, stable, and easily synthesized catalysts for hydrogen evolution reactions(HER) remains a significant challenge. This study explored the synthesis of nitrogen-doped MXene-based composite catalysts for enhanced HER performance. By thermally decomposing RuCl_(3) coordinated with melamine and formaldehyde resin, we successfully introduced nitrogen-doped carbon(N–C) with highly dispersed ruthenium(Ru) onto the MXene surface. The calcination temperature played a crucial role in controlling the size of Ru nanoparticles(Ru NPs) and the proportion of Ru single-atom(Ru SA), thereby facilitating the synergistic enhancement of HER performance by Ru NPs and Ru SA. The resulting catalyst prepared with a calcination temperature of 600℃, Ti_(3)C_(2)T_x-N/C-Ru-600(TNCR-600), exhibited exceptional HER activity(η10= 17 m V) and stability(160 h) under alkaline conditions. This work presented a simple and effective strategy for synthesizing composite catalysts, offering new insights into the design and regulation of high-performance Ru-based catalysts for hydrogen production.展开更多
Dynamic adsorption processes of reaction intermediates for alkaline hydrogen evolution(HER)catalysts are still confusing to understand.Here,we report a series of A-site ordered quadruple perovskite ruthenium-based ele...Dynamic adsorption processes of reaction intermediates for alkaline hydrogen evolution(HER)catalysts are still confusing to understand.Here,we report a series of A-site ordered quadruple perovskite ruthenium-based electrocatalysts ACu_(3)Ru_(4)O_(12)(A=Na,Ca,Nd,and La),with the target sample SrCu_(3)Ru_(4)O_(12)exhibiting a very low overpotential(46 mV@10 mA·cm^(-2))and excellent catalytic stability with little decays after 48-h durability test.Precise tuning A-site cations can change the average valence state of Cu and Ru,thus the plot of HER activity versus the average Ru valence number shows a volcano-type relationship.Density functional theory indicates that the Ru 4d orbitals of SrCu3Ru4O12possesses the most suitable d-band center position among the five samples,which might be the key parameter to determine the catalytic performance.Our work provides further insight into the discovering advanced,efficient hydrogen evolution catalysts through designing precise descriptor.展开更多
Water splitting with proton exchange membrane water electrolyzers(PEMWE)is regarded as a promising pathway for sustainable hydrogen conversion.Additionally,oxygen evolution reaction(OER)is considered as the dominant f...Water splitting with proton exchange membrane water electrolyzers(PEMWE)is regarded as a promising pathway for sustainable hydrogen conversion.Additionally,oxygen evolution reaction(OER)is considered as the dominant factor during the whole process due to the sluggish kinetics.Among the catalysts,Rubased catalysts draw special attention because of their excellent activity and relatively low price.However,the limited stability impedes their further commercialization and tremendous efforts have been devoted to overcome this challenge.This review firstly introduces the basic mechanisms of OER.Then the evaluation protocols and techniques to investigate the stability of Ru-based catalysts are summarized.A detailed elucidation of the possible degradation mechanisms is also critically analyzed.Furthermore,effective strategies to design durable Ru-based catalysts for acidic OER are discussed.Such as heteroatom doping,phase and facet engineering,heterostructure building and support optimization.Finally,promises,perspectives and challenges in developing highly durable Ru-based catalysts for acidic OER are outlined.展开更多
We must urgently synthesize highly efficient and stable oxygen-evolution reaction(OER) catalysts for acidic media. Herein, we constructed a series of Ti mesh(TM)-supported RuO_(2)/CoMo_(y)O_(x) catalysts(RuO_(2)/CoMo_...We must urgently synthesize highly efficient and stable oxygen-evolution reaction(OER) catalysts for acidic media. Herein, we constructed a series of Ti mesh(TM)-supported RuO_(2)/CoMo_(y)O_(x) catalysts(RuO_(2)/CoMo_(y)O_(x)/TM) with heterogeneous structures. By optimizing the ratio of Co to Mo, RuO_(2)/CoMO_(2)O_(x)/TM with low Ru loading(0.079 mg/cm^(2)) achieves remarkable OER performance(η = 243 mV at 10 mA/cm^(2)) and high stability(300 h @ 10 mA/cm^(2)) in 0.5 mol/L H_(2)SO_(4) electrolyte. The activity of RuO_(2)/CoMo_yO_x/TM can be maintained for 50 h at 100 mA/cm^(2), and a water electrolyzer with RuO_(2)/CoMO_(2)O_(x)/TM as anode can operate for 40 h at 100 mA/cm~2, suggesting the remarkable OER durability of RuO_(2)/CoMo__(y)O__(x)/TM in acidic electrolyte. Owing to the heterogeneous interface between CoMO_(2)O_(x) and RuO_(2), the electronic structure of Ru atoms was optimized and electron-rich Ru was formed. With modulated electronic properties, the dissociation energy of H_(2)O is weakened, and the OER barrier is lowered. This study provides the design of low-cost noble metal catalysts with long-term stability in an acidic environment.展开更多
A series of BaCe0_(3)modified with different rare earth elements(La,Y,Pr)were synthesized by coprecipitation and calcination and the effect of rare earth elements for catalytic ammonia synthesis under mild conditions ...A series of BaCe0_(3)modified with different rare earth elements(La,Y,Pr)were synthesized by coprecipitation and calcination and the effect of rare earth elements for catalytic ammonia synthesis under mild conditions was studied.The ammonia synthesis performance tests show that 2.5%Ru/BaCe_(0.9)La_(0.1)O_(3-δ)catalyst(All the percentages of Ru in this article are in mass fraction)exhibits the highest ammonia synthesis rate(34 mmol/(g·h))at 3 MPa,450℃,and no sign of deactivation after 100 h of reaction.H_(2)-TPR and XPS analyses indicate that the introduction of La increases the amount of oxygen vacancies of the catalyst,which is beneficial to increasing the electron density of Ru surface.HRTEM analysis shows that the Ru particle size is reduced greatly after La is introduced,which facilitates the catalyst generating more Bs-type sites(active sites of Ru species for N=N dissociation).CO_(2)-TPD analysis indicates that BaCe_(0.9)La_(0.1)O_(3-δ)has stronger basicity,which promotes electrons transfer from support to Ru.This work provides an effective method for design and synthesis of Ru-based multi-element composite perovskite oxide catalysts.展开更多
In this work,DFT calculations were used firstly to simulate the nitrogen coordinated metal single-atom catalysts(M-N_(x)SACs,M=Hg,Cu,Au,and Ru) to predict their catalytic activities in acetylene hydrochlorination.The ...In this work,DFT calculations were used firstly to simulate the nitrogen coordinated metal single-atom catalysts(M-N_(x)SACs,M=Hg,Cu,Au,and Ru) to predict their catalytic activities in acetylene hydrochlorination.The DFT results showed that Ru-N_(x)SACs had the best catalytic performance among the four catalysts,and Ru-N_(x)SACs could effectively inhibit the reduction of ruthenium cation.To verify the DFT results,Ru-N_(x)SACs were fabricated by pyrolyzing MOFs in-situ spatially confined metal precursors.The N coordination environment could be controlled by changing the pyrolysis temperature.Catalytic performance tests indicated that low N coordination number(Ru-N_(2),Ru-N_(3))exhibited excellent catalytic activity and stability compared to RuCl_(3)catalyst.DFT calculations further revealed that Ru-N_(2)and Ru-N_(3)had a tendency to activate HCl at the first step of reaction,whereas Ru-N4tended to activate C_(2)H_(2).These findings will serve as a reference for the design and control of metal active sites.展开更多
Electrolytic water splitting(EWS)is an attractive and promising technique for the production of hydrogen energy.Nevertheless,the sluggish kinetic rate of hydrogen/oxygen evolution reactions leads to a high overpotenti...Electrolytic water splitting(EWS)is an attractive and promising technique for the production of hydrogen energy.Nevertheless,the sluggish kinetic rate of hydrogen/oxygen evolution reactions leads to a high overpotential and low energy efficiency.Up to date,Pt/Ir-based nanocatalysts have become the state-of-the-art EWS catalysts,but disadvantages such as high cost and low earth abundance greatly limit their applications in EWS devices.As an attractive candidate for the Pt/Ir catalysts,series of Ru-based nanomaterials have aroused much attention for their low price,Pt-like hydrogen bond strength,and high EWS activity.In particular,Ru-doped functional porous materials have been becoming one of the most representative EWS catalysts,which can not only achieve the dispersion and adjustment for active Ru sites,but also simultaneously solve the problems of mass transfer and catalytic conversion in EWS.In this review,the design and preparation strategies of Ru-doped functional porous materials toward EWS in recent years are summarized,including Ru-doped metal organic frameworks(MOFs),Ru-doped porous organic polymers(POPs),and their derivatives.Meanwhile,detailed structure–activity relationships induced by the tuned geometric/electronic structures of Ru-doped functional porous materials are further depicted in this review.Last but not least,the challenges and perspectives of Ru-doped functional porous materials catalysts are reasonably proposed to provide fresh ideas for the design of Ru-based EWS catalysts.展开更多
Demethoxylation was kinetically and spectroscopically studied over three catalysts with different Ru^(0)/Ru^(δ+) ratios.In-situ spectroscopic tests demonstrated that the synergy between Ru^(0)and Ru^(δ+) was crucial...Demethoxylation was kinetically and spectroscopically studied over three catalysts with different Ru^(0)/Ru^(δ+) ratios.In-situ spectroscopic tests demonstrated that the synergy between Ru^(0)and Ru^(δ+) was crucial,and Ru^(0) was in charge of H_(2) activation and adsorption of aromatic ring while Ru^(δ+) adsorbed with O in methoxyl.A Langmuir-Hinshelwood kinetic model was proposed,and ratio of Ru^(0)/Ru^(δ+) was the key in deciding the rate-determining step(RDS):i)desorp-tion of toluene was RDS over catalyst with highRu^(0)ratio;ii)dissociation of H_(2) was RDS over Ru^(δ+) enriched catalyst;iii)demethoxylation was rate-determined by CO water-gas shift (WGS) when Ru^(0)/Ru^(δ+) approached~1.The best perfor-mance was obtained over Ru/NiAl_(2)O_(4)-200,which effectively enabled both C-O bond activation and rapid recovery of adsorption sites for aromatic rings.Finally,in-situ DRIFT studies on methoxy decomposition and CO-WGS unraveled that the electronic composition of Ru was more stable in Ru/NiAl_(2)O_(4)-200 which contributes to its excellence.展开更多
Developing highly efficient,cost-effective,and stable electrocatalysts for hydrogen evolution reaction(HER)is of considerable importance but remains challenging.Herein,we report the fabrication of a robust Ru-based el...Developing highly efficient,cost-effective,and stable electrocatalysts for hydrogen evolution reaction(HER)is of considerable importance but remains challenging.Herein,we report the fabrication of a robust Ru-based electrocatalyst,which comprises heterostructured Ru-Ru_(2)P nanoparticles that are embedded in the N,P-codoped carbon nanofibers(CNFs),through a synthetic strategy involving electrospinning and temperature-controlled pyrolysis treatment.The as-prepared Ru-Ru_(2)P catalyst(Ru-Ru_(2)P@CNFs)shows excellent HER catalytic activities with low overpotentials of 11 and 14 mV in acidic and alkaline media,respectively,to achieve a current density of 10 mA cm^(−2),which are superior to the individual components of pure Ru and Ru_(2)P catalysts.Density functional theory calculations demonstrate the existence of electronic coupling effect between Ru and Ru_(2)P at the heterointerfaces,leading to a well-modulated electronic structure with optimized hydrogen adsorption strength and enhanced electrical conductivity for efficient HER electrocatalysis.In addition,the overall synthetic strategy can be generalized for the synthesis of a series of transitional metal phosphide-based nanofibers,thereby holding a remarkable capacity for various potential applications.展开更多
The controllable synthesis of oxygen evolution reaction(OER)electrocatalyst is an urgent need to advance the develop-ment of sustainable energy conversion and storage.However,the OER efficiency in acidic media is seri...The controllable synthesis of oxygen evolution reaction(OER)electrocatalyst is an urgent need to advance the develop-ment of sustainable energy conversion and storage.However,the OER efficiency in acidic media is seriously hindered by slow reaction kinetics.The traditional acidic OER electrocatalysts are more prone to be oxidized and corroded as results of unstable carrier structures and variable electronic states of active species.Herein,a high-performing biochar aerogel(BA)based electrocatalyst were realistically designed and synthetized via joint utilization of the terrestrial lignin and seaweed polysaccharide as carbon sources.Originating from the induction effect of"egg-box"structure in alginate and the self-template effect of lignosulfonate,the BA decorated with Ru/RuS_(2)particles was synthesized triumphantly.The as-synthesized electrocatalyst required a low overpotential of 228 mV to attain 10 mA cm^(−2)in 0.5 M H_(2)SO_(4)and exhibited a good stability for over 12,000 s.The good activity was strongly dependent on the assembled unique two-dimensional/three-dimensional(2D/3D)channels in carbon aerogels.Notably,the numerous defective sites at carbon could strongly interact with the Ru/RuS_(2)heterojunction for remarkably enhancing the catalytic activity and stability of whole catalytic system in acidic media.This work puts forward a novel and effective strategy towards the enhancement of the acidic OER process by rational regu-lations of the BA and the coupling effect in micro-interface.展开更多
While supported-noble-metal catalysts have been widely investigated in hydrotreating reactions,a crucial issue that the catalytic system is still confronted with is developing an efficient approach to gain the high di...While supported-noble-metal catalysts have been widely investigated in hydrotreating reactions,a crucial issue that the catalytic system is still confronted with is developing an efficient approach to gain the high dispersion of noble metals under reducing conditions.In this work,Ru was supported on two MnOx with different specific surface areas(SSAs),and a much higher dispersion of Ru(83%,in contrast to 42%of the other one)was surprisingly observed over MnO with much lower SSA(around one-third of the other one).A suite of complementary characterizations demonstrates that,compared with the catalyst with high SSA(Ru/MnO-H),the MnO in the one with lower SSA(Ru/MnO-L)contains enriched surface oxygen that creates more abundant sites and bears stronger strength to anchor Ru species,mitigating the aggregation of Ru under reducing condition.This not only enriched active sites(i.e.,exposed Ru),but also created a more electron-deficient Ru domain and thus enhanced the redox property of the surface,leading to the lower barrier for C–O bond hydrogenolysis.In the hydrogenolysis of diphenyl ether,Ru/MnO-L exhibited significantly enhanced activity(i.e.,6 folds of Ru/MnO-H)and high stability.This work provides an approach to regulate the surface chemistry of support for the high dispersion of supported metal.展开更多
基金supported by the National Natural Science Foundation of China(No.22378308)Jing-Jin-Ji Regional Integrated Environmental Improvement-National Science and Technology Major Project(No.2024ZD1200301–2)the Scientific and Technological Project of Yunnan Precious Metal Laboratory(No.YPML2023050202)。
文摘A comprehensive understanding of the structure and dynamic evolution of catalytic active sites is vital for advancing the study of liquid-phase acetylene hydrochlorination.Here,we successfully developed a Ru-DIPEA/TMS catalyst optimised through systematic composition and condition tuning,demonstrating exceptional performance with 95.5%C_(2)H_(2)conversion and sustaining over 91.1%activity along with nearly 100%selectivity for VCM during a continuous 900-h test.Using a combination of characterisation techniques,including UV–vis spectroscopy,FT-IR spectroscopy,X-ray photoelectron spectroscopy,singlecrystal X-ray diffraction,and X-ray absorption spectroscopy,along with density functional theory(DFT)calculations,the structure and dynamic behaviour of the active sites were thoroughly investigated under the synergistic influence of ligands and HCl.The results revealed that HCl activation induces a significant structural transformation of the active sites,leading to the formation of a hexacoordinate complex,Ru(CO)_(2)C_(12)(C_(6)H_(15)N·HCl)_(2).DFT calculations further elucidated the mechanism underlying active site formation,revealing that an increased electron density around the Ru centre and corresponding changes in its coordination environment play critical roles in enhancing catalyst stability and activity.This study contributes to a deeper understanding of the structural basis of active site evolution during acetylene hydrochlorination,offering both practical insights into industrial applications and foundational knowledge for advancing liquid-phase catalysis.
基金financially supported by the Key Research and Development Program of Hainan Province(No.ZDYF2022GXJS006)the National Natural Science Foundation of China(Nos.52231008,52201009 and 52001227)+2 种基金Hainan Provincial Natural Science Foundation of China(No.223RC401)the Education Department of Hainan Province(No.Hnky2023ZD-2)the Starting Research Funds of the Hainan University of China(Nos.KYQD(ZR)-21105 and XJ2300002951)。
文摘Oxygen evolution reaction(OER)is a kinetically harsh four-electron anode reaction that requires a large overpotential to provide current and is of great importance in renewable electrochemical technique.Ir/Rubased perovskite oxides hold great significance for application as OER electrocatalysts,due to that their multimetal-oxide forms can reduce the use of noble metals,and their compositional tunability can modulate the electronic structure and optimize OER performance.However,high operating potentials and corrosive environments pose a serious challenge to the development of durable Ir-based and Ru-based perovskite electrocatalysts.Tremendous efforts have been dedicated to improving the Ir/Ru-based perovskite activity to enhance the efficiency;however,progress in improving the durability of Ir/Ru-based perovskite electrocatalysts has been rather limited.In this review,the recent research progress of Ir/Ru-based perovskites is reviewed from the perspective of heteroatom doping,structural modulation,and formation of heterostructures.The dissolution mechanism studies of Ir/Ru and experimental attempts to improve the durability of Ir/Ru-based perovskite electrocatalysts are discussed.Challenges and outlooks for further developing Ru-and Irbased perovskite oxygen electrocatalysts are also presented.
文摘Series of carbon nanotube supported Ru-based catalysts were prepared by impregnation method and applied successfully for complete removal of CO by CO selective methanation from H2-rich gas stream conducted in a fixed-bed quartz tubular reactor at ambient pressure. It was found that the metal promoter, reduction temperature and metal loading affected the catalytic properties significantly. The most excellent performance was presented by 30 wt% Ru-Zr/CNTs catalyst reduced at 350 ℃. Since it decreased CO concentration to below 10 ppm from 12000 ppm by CO selective methanation at the temperature range of 180-240 ℃, and kept CO selectivity higher than 85% at the temperature below 200 ℃. Characterization using XRD, TEM, H2-TPR and XPS suggests that Zr modification of Ru/CNTs results in the weakening of the interaction between Ru and CNTs, a higher Ru dispersion and the oxidization of surface Ru. Amorphous and high dispersed Ru particles with small size were obtained for 30 wt% Ru-Zr/CNTs catalyst reduced at 350 ℃, leading to excellent catalytic performance in CO selective methanation.
基金partly supported by the National Natural Science Foundation of China(NSFCs,52202050,52122308,21905253,51973200)the China Postdoctoral Science Foundation(2022TQ0286)the Natural Science Foundation of Henan(202300410372)。
文摘Water electrolysis using proton-exchange membranes is one of the most promising technologies for carbon-neutral and sustainable energy production.Generally,the overall efficiency of water splitting is limited by the oxygen evolution reaction(OER).Nevertheless,a trade-off between activity and stability exists for most electrocatalytic materials in strong acids and oxidizing media,and the development of efficient and stable catalytic materials has been an important focus of research.In this view,gaining in-depth insights into the OER system,particularly the interactions between reaction intermediates and active sites,is significantly important.To this end,this review introduces the fundamentals of the OER over Ru-based materials,including the conventional adsorbate evolution mechanism,lattice oxygen oxidation mechanism,and oxide path mechanism.Moreover,the up-to-date progress of representative modifications for improving OER performance is further discussed with reference to specific mechanisms,such as tuning of geometric,electronic structures,incorporation of proton acceptors,and optimization of metal-oxygen covalency.Finally,some valuable insights into the challenges and opportunities for OER electrocatalysts are provided with the aim to promote the development of next-generation catalysts with high activity and excellent stability.
基金the National Natural Science Foundation of China(No.22102215)the Fundamental Research Funds for the Central Universities(Nos.21CX06013A and 22CX03001A)the State Key Laboratory of Heavy Oil Processing and the Key Project of China National Key R&D Plan(No.2018YFE0118200).
文摘The fundamental insights of the reaction mechanism,especially the synergistic effect between oxygen vacancies and basic sites,are highly promising yet challenging for Ru-based catalysts during carbon dioxide(CO_(2))methanation.Herein,a series of Rubased catalysts were employed to study the mechanism of CO_(2) methanation.It is found that Ru/CeO_(2) catalyst exhibits a much higher CO_(2) conversion(86%)and CH4 selectivity(100%),as well as excellent stability of 30 h due to the existence of abundant oxygen vacancies and weak basic sites.Additionally,the in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and density functional theory(DFT)calculations reveal that the formate formation step dominated the hydrogenation route on Ru/CeO_(2) catalyst,and the b-HCOO^(*)could be the key intermediate due to b-HCOO^(*)is more easily hydrogenated to methane than m-HCOO^(*).The systematic study marks the significance of precise tailoring of the synergistic relationship between oxygen vacancies and basic sites for achieving the desired performance in CO_(2) methanation.
基金support from the Shenzhen Science and Technology Research Grant(No.JCYJ20200109140416788)the Shenzhen Fundamental Research Program(No.GXWD20201231165807007-20200807111854001)+1 种基金the Natural Science Foundation of Shenzhen(JCYJ20190813110605381)the National Natural Science Foundation of China(52102201).
文摘Green hydrogen energy developed through electrochemistry is one of the solutions to current energy problems.The less noble metal ruthenium(Ru)plays an important role in alkaline electrocatalytic hydrogen evolution reaction(HER)as an effective electrocatalyst.Nevertheless,the high cost(>110 RMB per gram)hinders the large-scale application of Ru in industrial hydrogen production.Moreover,the strong adsorption of OH*in-termediates over Ru limits the electrocatalytic performance in alkaline HER.Here,we report the Mo-doped Ru nanocluster embedded on N-doped carbon framework(RuMo/NC)as alkaline HER catalyst,which shows excellent catalytic performance with an overpotential of 24.2 mV to reach 10 mA cm-2 with only 0.4 wt%o of Ru,much lower than that of most reported Ru-based catalysts.DFT calculations reveal the introduction of Mo has improved the activity by alleviating the poisoning effect of OH*over Ru in HER.Through fully utilizing Ru in the catalyst,this work marks a step forward in the development of Ru-based catalysts in alkaline HER.
基金financially supported by the National Key R&D Program of China (No.2018YFA0209402)the National Natural Science Foundation of China (Nos.22088101, 22175132, 22072028)。
文摘Hydrogen has emerged as a promising environmentally friendly energy source. The development of lowcost, highly active, stable, and easily synthesized catalysts for hydrogen evolution reactions(HER) remains a significant challenge. This study explored the synthesis of nitrogen-doped MXene-based composite catalysts for enhanced HER performance. By thermally decomposing RuCl_(3) coordinated with melamine and formaldehyde resin, we successfully introduced nitrogen-doped carbon(N–C) with highly dispersed ruthenium(Ru) onto the MXene surface. The calcination temperature played a crucial role in controlling the size of Ru nanoparticles(Ru NPs) and the proportion of Ru single-atom(Ru SA), thereby facilitating the synergistic enhancement of HER performance by Ru NPs and Ru SA. The resulting catalyst prepared with a calcination temperature of 600℃, Ti_(3)C_(2)T_x-N/C-Ru-600(TNCR-600), exhibited exceptional HER activity(η10= 17 m V) and stability(160 h) under alkaline conditions. This work presented a simple and effective strategy for synthesizing composite catalysts, offering new insights into the design and regulation of high-performance Ru-based catalysts for hydrogen production.
基金Project supported financially by the National Key Research and Development Program of China(Grant No.2023YFA1406000)the National Natural Science Foundation of China(Grant Nos.22171283 and 12474002)+3 种基金the Fundamental Research Funds for the Central Universities(Grant Nos.2023ZCJH03 and 2021XD-A041)the Fund of State Key Laboratory of Information Photonics and Optical Communications(Beijing University of Posts and Telecommunications,China)the Teaching Reform Projects at BUPT(Grant No.2022CXCYB03)the BUPT Excellent Ph.D.Students Foundation(Grant No.CX2023108)。
文摘Dynamic adsorption processes of reaction intermediates for alkaline hydrogen evolution(HER)catalysts are still confusing to understand.Here,we report a series of A-site ordered quadruple perovskite ruthenium-based electrocatalysts ACu_(3)Ru_(4)O_(12)(A=Na,Ca,Nd,and La),with the target sample SrCu_(3)Ru_(4)O_(12)exhibiting a very low overpotential(46 mV@10 mA·cm^(-2))and excellent catalytic stability with little decays after 48-h durability test.Precise tuning A-site cations can change the average valence state of Cu and Ru,thus the plot of HER activity versus the average Ru valence number shows a volcano-type relationship.Density functional theory indicates that the Ru 4d orbitals of SrCu3Ru4O12possesses the most suitable d-band center position among the five samples,which might be the key parameter to determine the catalytic performance.Our work provides further insight into the discovering advanced,efficient hydrogen evolution catalysts through designing precise descriptor.
基金financially supported by National Natural Science Foundation of China(Nos.22122202,22072051,21972051)。
文摘Water splitting with proton exchange membrane water electrolyzers(PEMWE)is regarded as a promising pathway for sustainable hydrogen conversion.Additionally,oxygen evolution reaction(OER)is considered as the dominant factor during the whole process due to the sluggish kinetics.Among the catalysts,Rubased catalysts draw special attention because of their excellent activity and relatively low price.However,the limited stability impedes their further commercialization and tremendous efforts have been devoted to overcome this challenge.This review firstly introduces the basic mechanisms of OER.Then the evaluation protocols and techniques to investigate the stability of Ru-based catalysts are summarized.A detailed elucidation of the possible degradation mechanisms is also critically analyzed.Furthermore,effective strategies to design durable Ru-based catalysts for acidic OER are discussed.Such as heteroatom doping,phase and facet engineering,heterostructure building and support optimization.Finally,promises,perspectives and challenges in developing highly durable Ru-based catalysts for acidic OER are outlined.
基金supported by National Nature Science Foundation of China(22379106)Carbon Energy Technology Co.,Ltd.(0501001107)。
文摘We must urgently synthesize highly efficient and stable oxygen-evolution reaction(OER) catalysts for acidic media. Herein, we constructed a series of Ti mesh(TM)-supported RuO_(2)/CoMo_(y)O_(x) catalysts(RuO_(2)/CoMo_(y)O_(x)/TM) with heterogeneous structures. By optimizing the ratio of Co to Mo, RuO_(2)/CoMO_(2)O_(x)/TM with low Ru loading(0.079 mg/cm^(2)) achieves remarkable OER performance(η = 243 mV at 10 mA/cm^(2)) and high stability(300 h @ 10 mA/cm^(2)) in 0.5 mol/L H_(2)SO_(4) electrolyte. The activity of RuO_(2)/CoMo_yO_x/TM can be maintained for 50 h at 100 mA/cm^(2), and a water electrolyzer with RuO_(2)/CoMO_(2)O_(x)/TM as anode can operate for 40 h at 100 mA/cm~2, suggesting the remarkable OER durability of RuO_(2)/CoMo__(y)O__(x)/TM in acidic electrolyte. Owing to the heterogeneous interface between CoMO_(2)O_(x) and RuO_(2), the electronic structure of Ru atoms was optimized and electron-rich Ru was formed. With modulated electronic properties, the dissociation energy of H_(2)O is weakened, and the OER barrier is lowered. This study provides the design of low-cost noble metal catalysts with long-term stability in an acidic environment.
基金Project supported by the National Natural Science Foundation of China(21671147)Natural Science Foundation of Shanxi Province(201901D211117)Coal Bed Methane Joint Foundation of Shanxi Province(2016012004).
文摘A series of BaCe0_(3)modified with different rare earth elements(La,Y,Pr)were synthesized by coprecipitation and calcination and the effect of rare earth elements for catalytic ammonia synthesis under mild conditions was studied.The ammonia synthesis performance tests show that 2.5%Ru/BaCe_(0.9)La_(0.1)O_(3-δ)catalyst(All the percentages of Ru in this article are in mass fraction)exhibits the highest ammonia synthesis rate(34 mmol/(g·h))at 3 MPa,450℃,and no sign of deactivation after 100 h of reaction.H_(2)-TPR and XPS analyses indicate that the introduction of La increases the amount of oxygen vacancies of the catalyst,which is beneficial to increasing the electron density of Ru surface.HRTEM analysis shows that the Ru particle size is reduced greatly after La is introduced,which facilitates the catalyst generating more Bs-type sites(active sites of Ru species for N=N dissociation).CO_(2)-TPD analysis indicates that BaCe_(0.9)La_(0.1)O_(3-δ)has stronger basicity,which promotes electrons transfer from support to Ru.This work provides an effective method for design and synthesis of Ru-based multi-element composite perovskite oxide catalysts.
基金supported by the National Natural Science Foundation of China (NSFC,22172082,21978137,22102074,and 21878162)Natural Science Foundation of Tianjin (20JCZDJC00770)+1 种基金Postdoctoral Research Foundation of China (2021M701776)NCC Fund (NCC2020FH05)。
文摘In this work,DFT calculations were used firstly to simulate the nitrogen coordinated metal single-atom catalysts(M-N_(x)SACs,M=Hg,Cu,Au,and Ru) to predict their catalytic activities in acetylene hydrochlorination.The DFT results showed that Ru-N_(x)SACs had the best catalytic performance among the four catalysts,and Ru-N_(x)SACs could effectively inhibit the reduction of ruthenium cation.To verify the DFT results,Ru-N_(x)SACs were fabricated by pyrolyzing MOFs in-situ spatially confined metal precursors.The N coordination environment could be controlled by changing the pyrolysis temperature.Catalytic performance tests indicated that low N coordination number(Ru-N_(2),Ru-N_(3))exhibited excellent catalytic activity and stability compared to RuCl_(3)catalyst.DFT calculations further revealed that Ru-N_(2)and Ru-N_(3)had a tendency to activate HCl at the first step of reaction,whereas Ru-N4tended to activate C_(2)H_(2).These findings will serve as a reference for the design and control of metal active sites.
基金supported by the National Natural Science Foundation of China (22234005 and 21974070)the Natural Science Foundation of Jiangsu Province (BK20222015)the Young Academic Leaders of the Qing Lan Project of Jiangsu Province (SUJIAOSHIHAN[2022]No.29)。
基金supported by the National Key Research and Development Program of China(No.2020YFB1506300)the National Natural Science Foundation of China(Nos.21971017,21922502,and 22075018)+2 种基金Young Elite Scientists Sponsorship Program by BAST(No.BYESS2023163)CNPC Innovation Found(No.2022DQ02-0606)Beijing Institute of Technology Research Fund Program.
文摘Electrolytic water splitting(EWS)is an attractive and promising technique for the production of hydrogen energy.Nevertheless,the sluggish kinetic rate of hydrogen/oxygen evolution reactions leads to a high overpotential and low energy efficiency.Up to date,Pt/Ir-based nanocatalysts have become the state-of-the-art EWS catalysts,but disadvantages such as high cost and low earth abundance greatly limit their applications in EWS devices.As an attractive candidate for the Pt/Ir catalysts,series of Ru-based nanomaterials have aroused much attention for their low price,Pt-like hydrogen bond strength,and high EWS activity.In particular,Ru-doped functional porous materials have been becoming one of the most representative EWS catalysts,which can not only achieve the dispersion and adjustment for active Ru sites,but also simultaneously solve the problems of mass transfer and catalytic conversion in EWS.In this review,the design and preparation strategies of Ru-doped functional porous materials toward EWS in recent years are summarized,including Ru-doped metal organic frameworks(MOFs),Ru-doped porous organic polymers(POPs),and their derivatives.Meanwhile,detailed structure–activity relationships induced by the tuned geometric/electronic structures of Ru-doped functional porous materials are further depicted in this review.Last but not least,the challenges and perspectives of Ru-doped functional porous materials catalysts are reasonably proposed to provide fresh ideas for the design of Ru-based EWS catalysts.
基金supported financially by the National Key Research and Development Program of China(No.2022YFA1504900)the NSFC of China(No.22072041,21832002)the Science and Technology Commission of Shanghai Municipality(10dz2220500).
文摘Demethoxylation was kinetically and spectroscopically studied over three catalysts with different Ru^(0)/Ru^(δ+) ratios.In-situ spectroscopic tests demonstrated that the synergy between Ru^(0)and Ru^(δ+) was crucial,and Ru^(0) was in charge of H_(2) activation and adsorption of aromatic ring while Ru^(δ+) adsorbed with O in methoxyl.A Langmuir-Hinshelwood kinetic model was proposed,and ratio of Ru^(0)/Ru^(δ+) was the key in deciding the rate-determining step(RDS):i)desorp-tion of toluene was RDS over catalyst with highRu^(0)ratio;ii)dissociation of H_(2) was RDS over Ru^(δ+) enriched catalyst;iii)demethoxylation was rate-determined by CO water-gas shift (WGS) when Ru^(0)/Ru^(δ+) approached~1.The best perfor-mance was obtained over Ru/NiAl_(2)O_(4)-200,which effectively enabled both C-O bond activation and rapid recovery of adsorption sites for aromatic rings.Finally,in-situ DRIFT studies on methoxy decomposition and CO-WGS unraveled that the electronic composition of Ru was more stable in Ru/NiAl_(2)O_(4)-200 which contributes to its excellence.
基金financially supported by the Natural Science Foundation of Zhejiang Province (LQ20B030001 and LY20E020002)China Postdoctoral Science Foundation (2021M702305)。
文摘Developing highly efficient,cost-effective,and stable electrocatalysts for hydrogen evolution reaction(HER)is of considerable importance but remains challenging.Herein,we report the fabrication of a robust Ru-based electrocatalyst,which comprises heterostructured Ru-Ru_(2)P nanoparticles that are embedded in the N,P-codoped carbon nanofibers(CNFs),through a synthetic strategy involving electrospinning and temperature-controlled pyrolysis treatment.The as-prepared Ru-Ru_(2)P catalyst(Ru-Ru_(2)P@CNFs)shows excellent HER catalytic activities with low overpotentials of 11 and 14 mV in acidic and alkaline media,respectively,to achieve a current density of 10 mA cm^(−2),which are superior to the individual components of pure Ru and Ru_(2)P catalysts.Density functional theory calculations demonstrate the existence of electronic coupling effect between Ru and Ru_(2)P at the heterointerfaces,leading to a well-modulated electronic structure with optimized hydrogen adsorption strength and enhanced electrical conductivity for efficient HER electrocatalysis.In addition,the overall synthetic strategy can be generalized for the synthesis of a series of transitional metal phosphide-based nanofibers,thereby holding a remarkable capacity for various potential applications.
基金the National Natural Science Foundation of China(No.32101451)the Shandong Provincial Natural Science Foundation(No.ZR2019BC007)+2 种基金the Postdoctoral Science Foundation of China(No.2018M632626)State Key Laboratory of Bio-Fibers and Eco-Textiles(Qingdao University)(No.ZKT31)the Taishan Scholar Program of Shandong Province.
文摘The controllable synthesis of oxygen evolution reaction(OER)electrocatalyst is an urgent need to advance the develop-ment of sustainable energy conversion and storage.However,the OER efficiency in acidic media is seriously hindered by slow reaction kinetics.The traditional acidic OER electrocatalysts are more prone to be oxidized and corroded as results of unstable carrier structures and variable electronic states of active species.Herein,a high-performing biochar aerogel(BA)based electrocatalyst were realistically designed and synthetized via joint utilization of the terrestrial lignin and seaweed polysaccharide as carbon sources.Originating from the induction effect of"egg-box"structure in alginate and the self-template effect of lignosulfonate,the BA decorated with Ru/RuS_(2)particles was synthesized triumphantly.The as-synthesized electrocatalyst required a low overpotential of 228 mV to attain 10 mA cm^(−2)in 0.5 M H_(2)SO_(4)and exhibited a good stability for over 12,000 s.The good activity was strongly dependent on the assembled unique two-dimensional/three-dimensional(2D/3D)channels in carbon aerogels.Notably,the numerous defective sites at carbon could strongly interact with the Ru/RuS_(2)heterojunction for remarkably enhancing the catalytic activity and stability of whole catalytic system in acidic media.This work puts forward a novel and effective strategy towards the enhancement of the acidic OER process by rational regu-lations of the BA and the coupling effect in micro-interface.
基金the National Natural Science Foundation of China(Nos.22025604,21976196,21936005,and 21878244)the fellowship of China Postdoctoral Science Foundation(No.2022M713308)the Special Project of Eco-environmental Technology for Emission Peak&Carbon Neutralization(No.RCEES-TDZ-2021-4).
文摘While supported-noble-metal catalysts have been widely investigated in hydrotreating reactions,a crucial issue that the catalytic system is still confronted with is developing an efficient approach to gain the high dispersion of noble metals under reducing conditions.In this work,Ru was supported on two MnOx with different specific surface areas(SSAs),and a much higher dispersion of Ru(83%,in contrast to 42%of the other one)was surprisingly observed over MnO with much lower SSA(around one-third of the other one).A suite of complementary characterizations demonstrates that,compared with the catalyst with high SSA(Ru/MnO-H),the MnO in the one with lower SSA(Ru/MnO-L)contains enriched surface oxygen that creates more abundant sites and bears stronger strength to anchor Ru species,mitigating the aggregation of Ru under reducing condition.This not only enriched active sites(i.e.,exposed Ru),but also created a more electron-deficient Ru domain and thus enhanced the redox property of the surface,leading to the lower barrier for C–O bond hydrogenolysis.In the hydrogenolysis of diphenyl ether,Ru/MnO-L exhibited significantly enhanced activity(i.e.,6 folds of Ru/MnO-H)and high stability.This work provides an approach to regulate the surface chemistry of support for the high dispersion of supported metal.
