Optimizing the structure and components is a prevalent strategy for increasing electrocatalytic energy-saving H 2 fuel production.One of the sustainable and efficient techniques is electrocatalytic water split-ting fo...Optimizing the structure and components is a prevalent strategy for increasing electrocatalytic energy-saving H 2 fuel production.One of the sustainable and efficient techniques is electrocatalytic water split-ting for H 2 generation,but it is still restricted by the kinetically sluggish OER.Due to the lower standard oxidation potential of−0.33 V,replacing the OER with anodic hydrazine oxidation reaction(HzOR)is an effective way to extensively reduce the use of electricity in water electrolysis.Through alloying,the semiconductor and adsorption characteristics of Cu,interlaced by Pd 2+solution on the Pd surface by pulsed laser ablation(PLA)in methanol,are selectively altered to maximize cathodic HER and anodic HzOR performance.The optimal Cu1Pd3/C ratio demonstrates outstanding HER performance with a low overpotential of 0.315 V at 10 mA cm^(−2),as well as an ultralow overpotential of 0.560 V for HzOR in 0.5 M N_(2) H_(4)/1.0 M KOH.Furthermore,the constructed HzOR-assisted electrolyzer cell with Cu1Pd3/C||Cu1Pd3/C as anode and cathode exhibits a cell voltage of 0.505 V at 10 mA cm^(−2) with exceptional en-durance over 5 h.The current study advances competent CuPd alloys as multifunctional electrocatalysts for H 2 fuel production using a HzOR-assisted energy-efficient electrolyzer.展开更多
Electrochemical overall water splitting for sustainable hydrogen generation is severely hindered by anode water electrooxidation with sluggish kinetics.Thus,using the thermodynamically favorable hydrazine oxidation re...Electrochemical overall water splitting for sustainable hydrogen generation is severely hindered by anode water electrooxidation with sluggish kinetics.Thus,using the thermodynamically favorable hydrazine oxidation reaction(HzOR)to substitute the oxygen evolution reaction(OER)has attracted ever-growing attention.Herein,well-defined copper selenide nanoflakes,in situ grown on copper foam(termed Cu_(x)Se/CF),were synthesized by a one-step selenization strategy,which are composed of nonstoichiometric Cu_(2-x)Se with stable Cu2Se berzelianite that show remarkable bifunctional activities for the hydrogen evolution reaction(HER)and HzOR electrocatalysis.Investigations into the mechanisms uncovered that the high copper deficiencies in the Cu_(2-x)Se phase make it both an excellent electron donor and acceptor,leading to faster electron transfers across the catalyst(electrode)-electrolyte interface,which greatly boosts the reaction kinetics of HER and HzOR processes.Meanwhile,the Cu2Se berzelianite phase plays a pivotal role in the long-term electrocatalytic operation for the HER and HzOR.Encouraged by this synergistic advantage,the CuxSe/CF catalysts were further employed as good bifunctional catalysts for electrocatalytic hydrazine-assisted overall water splitting with a low cell voltage of 0.49 V at 25 mA cm^(-2),as well as having good stability over 20 h,which indicates the broad potential for future industrialization of a sustainable hydrogen-based society.展开更多
The hydrazine oxidation reaction(HzOR)boasts a low theoretical working potential,rendering it promising for applications in energy-saving hydrogen production and treatment of hydrazine-containing wastewater.Herein,Ni ...The hydrazine oxidation reaction(HzOR)boasts a low theoretical working potential,rendering it promising for applications in energy-saving hydrogen production and treatment of hydrazine-containing wastewater.Herein,Ni species-incorporated CoP nanosheet arrays encapsulated in N-doped carbon layers grown on Ni foam(Ni-CoP@NC)have been synthesized.Due to the outstanding synergistic effect resulting from metal incorporation and N-doped carbon encapsulation,a high current density of 1 A cm^(-2)at low potentials of-143 mV and 51 mV for the hydrogen evolution reaction(HER)and HzOR is achieved by using Ni-CoP@NC,respectively.Furthermore,the Ni-CoP@NC-assembled hydrazine-assisted seawater electrolysis system exhibits a remarkable decrease in voltage input compared to conventional and other hybrid electrolysis devices,achieving an ultra-low voltage of just 0.49 V to attain a current density of 1 A cm^(-2).Remarkably,a five-fold cost reduction is offered by this system compared to conventional water electrolysis.Moreover,a novel multi-powered hydrogen production system is proposed,which consists of renewable energy sources,direct hydrazine fuel cells,rechargeable Zn-hydrazine batteries,and hydrazine-assisted seawater electrolysis.This system showcases the unique advantages of the HzOR and its potential contribution to electrochemical energy conversion technologies for sustainable energy supply.展开更多
Electrochemical H_(2) production from water splitting is an environmentally sustainable technique but remains a great challenge due to the sluggish anodic oxygen evolution reaction(OER).Replacing the OER with the ther...Electrochemical H_(2) production from water splitting is an environmentally sustainable technique but remains a great challenge due to the sluggish anodic oxygen evolution reaction(OER).Replacing the OER with the thermodynamically more favorable electrocatalytic oxidation process is an effective strategy for highly efficient H_(2) generation.Herein,Mn-doped CoS_(2) has predicted an excellent bifunctional electrocatalyst for the hydrogen evolution reaction(HER)and the hydrazine oxidation reaction(HzOR).With the introduction of Mn,the Gibbs free energy of the adsorbed H* and the potential rate-limiting step(the dehydrogenation of *NH_(2)NH_(2) to *NHNH_(2))for the HzOR process of the catalyst can be significantly reduced.As expected,the Mn-CoS_(2) catalyst exhibited excellent catalytic activity and robust long-term stability for the HER and HzOR.In detail,the Mn-CoS_(2) catalyst only acquired potentials of 46 and 77 mV versus the reversible hydrogen electrode for achieving a current density of 10 mA cm^(-2) for the cathodic HER and anodic HzOR,respectively.In addition,the Mn-CoS_(2) electrode only needs a cell voltage of 447 mV to output 200 mA cm^(-2) in the overall hydrazine splitting system as well as exhibits a robust longterm H_(2) production.This work provides theoretical guidance for the design of advanced bifunctional electrocatalysts and promotes high efficiency and energy-saving H_(2) production technology.展开更多
基金supported by Korea Basic Science Institute (National research Facilities and Equipment Center)grant funded by the Ministry of Education. (Nos.2019R1A6C1010042,2021R1A6C103A427)support from National Research Foundation of Korea (NRF), (Nos.2022R1A2C2010686,2022R1A4A3033528,2020R1I1A1A01065748,2021R1I1A1A01060380).
文摘Optimizing the structure and components is a prevalent strategy for increasing electrocatalytic energy-saving H 2 fuel production.One of the sustainable and efficient techniques is electrocatalytic water split-ting for H 2 generation,but it is still restricted by the kinetically sluggish OER.Due to the lower standard oxidation potential of−0.33 V,replacing the OER with anodic hydrazine oxidation reaction(HzOR)is an effective way to extensively reduce the use of electricity in water electrolysis.Through alloying,the semiconductor and adsorption characteristics of Cu,interlaced by Pd 2+solution on the Pd surface by pulsed laser ablation(PLA)in methanol,are selectively altered to maximize cathodic HER and anodic HzOR performance.The optimal Cu1Pd3/C ratio demonstrates outstanding HER performance with a low overpotential of 0.315 V at 10 mA cm^(−2),as well as an ultralow overpotential of 0.560 V for HzOR in 0.5 M N_(2) H_(4)/1.0 M KOH.Furthermore,the constructed HzOR-assisted electrolyzer cell with Cu1Pd3/C||Cu1Pd3/C as anode and cathode exhibits a cell voltage of 0.505 V at 10 mA cm^(−2) with exceptional en-durance over 5 h.The current study advances competent CuPd alloys as multifunctional electrocatalysts for H 2 fuel production using a HzOR-assisted energy-efficient electrolyzer.
基金supported by the National Natural Science Foundation of China(22179065 and 21875118)the Smart Sensing Interdisciplinary Science Center,Nankai University.
文摘Electrochemical overall water splitting for sustainable hydrogen generation is severely hindered by anode water electrooxidation with sluggish kinetics.Thus,using the thermodynamically favorable hydrazine oxidation reaction(HzOR)to substitute the oxygen evolution reaction(OER)has attracted ever-growing attention.Herein,well-defined copper selenide nanoflakes,in situ grown on copper foam(termed Cu_(x)Se/CF),were synthesized by a one-step selenization strategy,which are composed of nonstoichiometric Cu_(2-x)Se with stable Cu2Se berzelianite that show remarkable bifunctional activities for the hydrogen evolution reaction(HER)and HzOR electrocatalysis.Investigations into the mechanisms uncovered that the high copper deficiencies in the Cu_(2-x)Se phase make it both an excellent electron donor and acceptor,leading to faster electron transfers across the catalyst(electrode)-electrolyte interface,which greatly boosts the reaction kinetics of HER and HzOR processes.Meanwhile,the Cu2Se berzelianite phase plays a pivotal role in the long-term electrocatalytic operation for the HER and HzOR.Encouraged by this synergistic advantage,the CuxSe/CF catalysts were further employed as good bifunctional catalysts for electrocatalytic hydrazine-assisted overall water splitting with a low cell voltage of 0.49 V at 25 mA cm^(-2),as well as having good stability over 20 h,which indicates the broad potential for future industrialization of a sustainable hydrogen-based society.
基金supported by the National Natural Science Foundation of China(22179065)the Ph.D.Candidate Research Innovation Fund of NKU School of Materials Science and Engineering.
文摘The hydrazine oxidation reaction(HzOR)boasts a low theoretical working potential,rendering it promising for applications in energy-saving hydrogen production and treatment of hydrazine-containing wastewater.Herein,Ni species-incorporated CoP nanosheet arrays encapsulated in N-doped carbon layers grown on Ni foam(Ni-CoP@NC)have been synthesized.Due to the outstanding synergistic effect resulting from metal incorporation and N-doped carbon encapsulation,a high current density of 1 A cm^(-2)at low potentials of-143 mV and 51 mV for the hydrogen evolution reaction(HER)and HzOR is achieved by using Ni-CoP@NC,respectively.Furthermore,the Ni-CoP@NC-assembled hydrazine-assisted seawater electrolysis system exhibits a remarkable decrease in voltage input compared to conventional and other hybrid electrolysis devices,achieving an ultra-low voltage of just 0.49 V to attain a current density of 1 A cm^(-2).Remarkably,a five-fold cost reduction is offered by this system compared to conventional water electrolysis.Moreover,a novel multi-powered hydrogen production system is proposed,which consists of renewable energy sources,direct hydrazine fuel cells,rechargeable Zn-hydrazine batteries,and hydrazine-assisted seawater electrolysis.This system showcases the unique advantages of the HzOR and its potential contribution to electrochemical energy conversion technologies for sustainable energy supply.
基金financially supported by the National Natural Science Foundation of China(22075211,21601136,51971157,62005173,and 51621003)the Zhejiang Provincial Natural Science Foundation of China(LR19B060002)+5 种基金the Research Funds of Institute of Zhejiang University-QuzhouThe Guangdong Province Higher Vocational Colleges&Schools Pearl River Scholar Funded Scheme(2016)the Guangdong Third Generation Semiconductor Engineering Technology Development Center(2020GCZX007)the Science,Technology,and Innovation Commission of Shenzhen Municipality(RCBS20200714114818140)the China Postdoctoral Science Foundation(2019M663118)the School level Scientific Research Project of Shenzhen Institute of Information Technology(PT2019E002).
文摘Electrochemical H_(2) production from water splitting is an environmentally sustainable technique but remains a great challenge due to the sluggish anodic oxygen evolution reaction(OER).Replacing the OER with the thermodynamically more favorable electrocatalytic oxidation process is an effective strategy for highly efficient H_(2) generation.Herein,Mn-doped CoS_(2) has predicted an excellent bifunctional electrocatalyst for the hydrogen evolution reaction(HER)and the hydrazine oxidation reaction(HzOR).With the introduction of Mn,the Gibbs free energy of the adsorbed H* and the potential rate-limiting step(the dehydrogenation of *NH_(2)NH_(2) to *NHNH_(2))for the HzOR process of the catalyst can be significantly reduced.As expected,the Mn-CoS_(2) catalyst exhibited excellent catalytic activity and robust long-term stability for the HER and HzOR.In detail,the Mn-CoS_(2) catalyst only acquired potentials of 46 and 77 mV versus the reversible hydrogen electrode for achieving a current density of 10 mA cm^(-2) for the cathodic HER and anodic HzOR,respectively.In addition,the Mn-CoS_(2) electrode only needs a cell voltage of 447 mV to output 200 mA cm^(-2) in the overall hydrazine splitting system as well as exhibits a robust longterm H_(2) production.This work provides theoretical guidance for the design of advanced bifunctional electrocatalysts and promotes high efficiency and energy-saving H_(2) production technology.
