The conversion of urea-containing wastewater into clean hydrogen energy has gained increasing attention.However,challenges remain,particularly with sluggish catalytic kinetics and limited long-term stability of urea o...The conversion of urea-containing wastewater into clean hydrogen energy has gained increasing attention.However,challenges remain,particularly with sluggish catalytic kinetics and limited long-term stability of urea oxidation reaction(UOR).Herein,we report the loosely porous CoOOH nano-architecture(CoOOH LPNAs)with hydrophilic surface and abundant oxygen vacancies(Ov)on carbon fiber paper(CFP)by electrochemical reconstruction of the CoP nanoneedles precursor.The resulting three-dimensional electrode exhibited an impressively low potential of 1.38 V at 1000 mA·cm^(−2) and excellent durability for UOR.Furthermore,when tested in an anion exchange membrane(AEM)electrolyzer,it required only 1.53 V at 1000 mA·cm^(−2) for industrial urea-assisted water splitting and operated stably for 100 h without degrada-tion.Experimental and theoretical investigations revealed that rich oxygen vacancies effectively modulate the electronic structure of the CoOOH while creating unique Co3-triangle sites with Co atoms close together.As a result,the adsorption and desorption processes of reactants and intermediates in UOR could be finely tuned,thereby significantly reducing ther-modynamic barriers.Additionally,the superhydrophilic self-supported nanoarray structure facilitated rapid gas bubble release,improving the overall efficiency of the reaction and preventing potential catalyst detachment caused by bubble accumulation,thereby improving both catalytic activity and stability at high current densities.展开更多
Direct ethanol fuel cells(DEFCs)are a promising alternative to conventional energy sources,offering high energy density,environmental sustainability,and operational safety.Compared to methanol fuel cells,DEFCs exhibit...Direct ethanol fuel cells(DEFCs)are a promising alternative to conventional energy sources,offering high energy density,environmental sustainability,and operational safety.Compared to methanol fuel cells,DEFCs exhibit lower toxicity and a more mature preparation process.Unlike hydrogen fuel cells,DEFCs provide superior storage and transport feasibility,as well as cost-effectiveness,significantly enhancing their commercial viability.However,the stable C-C bond in ethanol creates a high activation energy barrier,often resulting in incomplete electrooxidation.Current commercial platinum(Pt)-and palladium(Pd)-based catalysts demonstrate low C-C bond cleavage efficiency(<7.5%),severely limiting DEFC energy output and power density.Furthermore,high catalyst costs and insufficient activity impede large-scale commercialization.Recent advances in DEFC anode catalyst design have focused on optimizing material composition and elucidating catalytic mechanisms.This review systematically examines developments in ethanol electrooxidation catalysts over the past five years,highlighting strategies to improve C1 pathway selectivity and C-C bond activation.Key approaches,such as alloying,nanostructure engineering,and interfacial synergy effects,are discussed alongside their mechanistic implications.Finally,we outline current challenges and future prospects for DEFC commercialization.展开更多
The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R(f-CB),functionalized multi-walled carbon nanotubes(f-MWCNT),and mesoporous carbon(PC-Zn-succini...The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R(f-CB),functionalized multi-walled carbon nanotubes(f-MWCNT),and mesoporous carbon(PC-Zn-succinic)by sodium borohydride chemical reduction method to improve the ethanol electrooxidation reaction(EOR)for direct ethanol fuel cell(DEFC).It was found that the particle size of the metals on f-MWCNT was 5.20 nm with good particle dispersion.The alloy formation of ternary catalyst was confirmed by XRD and more clearly described by SEM element mapping,which was relevant to the efficiency of the catalysts.Moreover,the mechanism of ethanol electrooxidation reaction based on the surface reaction was more understanding.The activity and stability for ethanol electrooxidation reaction(EOR)were investigated using cyclic voltammetry and chronoamperometry,respectively.The highest activity and stability for EOR were observed from Pt75Ru5Ni20/f-MWCNT due to a good metal-carbon interaction.Ru and Ni presented in Pt-Ru-Ni alloy improved the activity and stability of ternary catalysts for EOR.Moreover,the reduction of Pt content in ternary catalyst led to the catalyst cost deduction in DEFC.展开更多
Ni_(2)CoS_(4)was prepared by the liquid‑phase method and applied to the benzyl alcohol electro‑oxidation reaction(BAOR),demonstrating excellent catalytic activity[with a current density of 271 mA·cm^(-2)at 1.40 V...Ni_(2)CoS_(4)was prepared by the liquid‑phase method and applied to the benzyl alcohol electro‑oxidation reaction(BAOR),demonstrating excellent catalytic activity[with a current density of 271 mA·cm^(-2)at 1.40 V(vs RHE)]and long‑term stability.The S‑anion effect can regulate the charge distribution on the catalyst surface,thereby enhancing the additional adsorption capacity of OH-at the Co sites.By combining material characterization and theoretical calculations,it can be observed that this process can increase the concentration of the OH^(*)intermediate,accelerate the activation process of the Ni site,and ultimately achieve an improvement in overall activity and stability.展开更多
基金supported by the Applied Basic Research Program of Yunnan Province(202101BE070001-032)Yunnan Major Scientific and Technological Projects(No.202202AG050001).
文摘The conversion of urea-containing wastewater into clean hydrogen energy has gained increasing attention.However,challenges remain,particularly with sluggish catalytic kinetics and limited long-term stability of urea oxidation reaction(UOR).Herein,we report the loosely porous CoOOH nano-architecture(CoOOH LPNAs)with hydrophilic surface and abundant oxygen vacancies(Ov)on carbon fiber paper(CFP)by electrochemical reconstruction of the CoP nanoneedles precursor.The resulting three-dimensional electrode exhibited an impressively low potential of 1.38 V at 1000 mA·cm^(−2) and excellent durability for UOR.Furthermore,when tested in an anion exchange membrane(AEM)electrolyzer,it required only 1.53 V at 1000 mA·cm^(−2) for industrial urea-assisted water splitting and operated stably for 100 h without degrada-tion.Experimental and theoretical investigations revealed that rich oxygen vacancies effectively modulate the electronic structure of the CoOOH while creating unique Co3-triangle sites with Co atoms close together.As a result,the adsorption and desorption processes of reactants and intermediates in UOR could be finely tuned,thereby significantly reducing ther-modynamic barriers.Additionally,the superhydrophilic self-supported nanoarray structure facilitated rapid gas bubble release,improving the overall efficiency of the reaction and preventing potential catalyst detachment caused by bubble accumulation,thereby improving both catalytic activity and stability at high current densities.
基金supported by the National Natural Science Foundation of China(22472023,22202037)the Jilin Province Science and Technology Development Program(20250102077JC)the Fundamental Research Funds for the Central Universities(2412024QD014,2412023QD019).
文摘Direct ethanol fuel cells(DEFCs)are a promising alternative to conventional energy sources,offering high energy density,environmental sustainability,and operational safety.Compared to methanol fuel cells,DEFCs exhibit lower toxicity and a more mature preparation process.Unlike hydrogen fuel cells,DEFCs provide superior storage and transport feasibility,as well as cost-effectiveness,significantly enhancing their commercial viability.However,the stable C-C bond in ethanol creates a high activation energy barrier,often resulting in incomplete electrooxidation.Current commercial platinum(Pt)-and palladium(Pd)-based catalysts demonstrate low C-C bond cleavage efficiency(<7.5%),severely limiting DEFC energy output and power density.Furthermore,high catalyst costs and insufficient activity impede large-scale commercialization.Recent advances in DEFC anode catalyst design have focused on optimizing material composition and elucidating catalytic mechanisms.This review systematically examines developments in ethanol electrooxidation catalysts over the past five years,highlighting strategies to improve C1 pathway selectivity and C-C bond activation.Key approaches,such as alloying,nanostructure engineering,and interfacial synergy effects,are discussed alongside their mechanistic implications.Finally,we outline current challenges and future prospects for DEFC commercialization.
基金supported by the Institutional Research Grant(Thailand Research Fund:IRG598004)
文摘The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R(f-CB),functionalized multi-walled carbon nanotubes(f-MWCNT),and mesoporous carbon(PC-Zn-succinic)by sodium borohydride chemical reduction method to improve the ethanol electrooxidation reaction(EOR)for direct ethanol fuel cell(DEFC).It was found that the particle size of the metals on f-MWCNT was 5.20 nm with good particle dispersion.The alloy formation of ternary catalyst was confirmed by XRD and more clearly described by SEM element mapping,which was relevant to the efficiency of the catalysts.Moreover,the mechanism of ethanol electrooxidation reaction based on the surface reaction was more understanding.The activity and stability for ethanol electrooxidation reaction(EOR)were investigated using cyclic voltammetry and chronoamperometry,respectively.The highest activity and stability for EOR were observed from Pt75Ru5Ni20/f-MWCNT due to a good metal-carbon interaction.Ru and Ni presented in Pt-Ru-Ni alloy improved the activity and stability of ternary catalysts for EOR.Moreover,the reduction of Pt content in ternary catalyst led to the catalyst cost deduction in DEFC.
文摘Ni_(2)CoS_(4)was prepared by the liquid‑phase method and applied to the benzyl alcohol electro‑oxidation reaction(BAOR),demonstrating excellent catalytic activity[with a current density of 271 mA·cm^(-2)at 1.40 V(vs RHE)]and long‑term stability.The S‑anion effect can regulate the charge distribution on the catalyst surface,thereby enhancing the additional adsorption capacity of OH-at the Co sites.By combining material characterization and theoretical calculations,it can be observed that this process can increase the concentration of the OH^(*)intermediate,accelerate the activation process of the Ni site,and ultimately achieve an improvement in overall activity and stability.
