Developing high-performance and cost-effective electrocatalysts for the hydrogen evolution reaction(HER)is highly essential for the large-scale application of water splitting.In this work,surficial-enriched ruthenium(...Developing high-performance and cost-effective electrocatalysts for the hydrogen evolution reaction(HER)is highly essential for the large-scale application of water splitting.In this work,surficial-enriched ruthenium(Ru)catalyst was developed on octahedral cerium dioxide(CeO_(2))through a combination of hydrothermal synthesis and ultrafast(60 s)wet impregnation approaches,utilizing H_(2)O_(2) as a facilitator(Ru/CeO_(2)-H_(2)O_(2)).Experimental characterization and density functional theory(DFT)calculation demonstrate that the created oxygen vacancy(Ov)and strong electronic interactions play crucial roles in improving catalytic activity and stability.In particular,the specific octahedral morphology and surficial-enriched Ru enhance the exposure of abundant active sites,thereby accelerating the reaction kinetics.The as-synthesized Ru/CeO_(2)-H_(2)O_(2) demonstrated commendable catalytic performance in both 1 M KOH and 1 M KOH+seawater with small overpotentials of 37 and 47 mV,respectively,to attain a current density of 10 mA cm-2.Furthermore,it exhibited remarkable long-term stability at both 10 mA cm-2 and 500 mA cm-2,and demonstrated the ability to drive overall water splitting when coupled with sustainable energy sources.Therefore,this study presents a promising approach for constructing high noble-metal utilization efficiency with a specific support,offering potential for enhanced sustainable energy applications.展开更多
CeO_(x)as a(co-)catalyst has been proved a promising material toward the oxygen evolution reaction(OER)in water splitting.In this study,a novel two-step method for the synthesis of cerium oxide nanoparticles in-situ g...CeO_(x)as a(co-)catalyst has been proved a promising material toward the oxygen evolution reaction(OER)in water splitting.In this study,a novel two-step method for the synthesis of cerium oxide nanoparticles in-situ generatedon CoP nanosheets toward OER is presented.Interestingly,Ce ions were gradually hydrolyzed and oxidized under the action of alkaline ligand andsolvothermal environment,and eventually existed in the form of CeO_(x)on the 2D Co-MOF nanosheets in the first step.In the followed selective phosphating process,2D Co-MOF nanosheets act as the template are transformed into CoP nanosheets but CeO_(x)is still maintained.Optimal CeO_(x)/CoP nanosheets exhibit low OER overpotential,small Tafel slope and robust durability.Furthermore,in situ electrochemical Raman spectroscopy demonstrates the transformation of the active catalytic species during the oxidation process.This in situ generation of a cocatalyst and selective phosphidation strategy provides some guidelines for the designing of highly efficient catalysts for OER and even other explorations.展开更多
Utilizing transition metal elements(Ni,Fe,Co)to design heterojunction catalysts is an effective approach for enhancing the efficiency of electrocatalytic water splitting.In this study,an n–n type junction was constru...Utilizing transition metal elements(Ni,Fe,Co)to design heterojunction catalysts is an effective approach for enhancing the efficiency of electrocatalytic water splitting.In this study,an n–n type junction was constructed uniformly in a CoFe-LDH@NiCoP/NF electrode through electrodeposition.This not only enhanced the conductivity and kinetic performance but also improved the electrocatalytic stability of the catalysts.The presence of an n–n type junction facilitates electron rearrangement at the heterogeneous interface,resulting in the transfer of electrons from CoFe-LDH to NiCoP.As a result,the activity of overall water splitting with CoFe-LDH@NiCoP/NF as both the cathode and anode only required 1.735 V to reach 200 mA cm^(−2);the voltage dropped by only 13 mV after 3000 CV cycles and the current density decreased by a mere 18%in 138 h at 270 mA cm^(−2).Therefore,the utilization of an n–n junction would provide more possibilities to regulate the electronic structure of electrocatalysts,especially in alkaline solutions.展开更多
The development of porous metal phosphides with abundant active sites is of great importance for efficient electrocatalytic water splitting.In this work,three-dimensional(3D)-ordered mesoporous irondoped cobalt phosph...The development of porous metal phosphides with abundant active sites is of great importance for efficient electrocatalytic water splitting.In this work,three-dimensional(3D)-ordered mesoporous irondoped cobalt phosphide(meso-Co_(2-x)Fe_(x)P)was prepared by a nanocasting strategy using SBA-15 as the hard template combined with a subsequent phosphidation.The unique mesoporous structure of the meso-Co_(2-x)Fe_(x)P electrocatalyst resulted in the exposure of abundant active sites and favorable mass transfer for the electrocatalytic process.Due to the synergy effects of the mesoporous structure and ternary component,the meso-Co_(2-x)Fe_(x)P exhibited outstanding electrocatalytic activity with low overpotentials of 93.7 mV and 266.4 mV at a current density of 10 mA cm^(-2) for HER and OER,respectively.In addition,meso-Co_(2-x)Fe_(x)P showed excellent overall water splitting activity with an external voltage of 1.58 V at a current density of 10 mA cm^(-2),superior to the electrolytic cell consisting of 20%Pt/C and RuO_(2),demonstrating it has great potential for practical application in overall water splitting.展开更多
基金the funding support from the National Natural Science Foundation of China(52371227,52272222,52102273 and 52072197)Taishan Scholar Young Talent Program(tsqn201909114)+2 种基金Shandong Province“Double-Hundred Talent Plan”(WST2020003)the Natural Science Foundation of Shandong Province of China(ZR2021QE081)Shandong College Students Innovation and Entrepreneurship Training Program(S202410426056).
文摘Developing high-performance and cost-effective electrocatalysts for the hydrogen evolution reaction(HER)is highly essential for the large-scale application of water splitting.In this work,surficial-enriched ruthenium(Ru)catalyst was developed on octahedral cerium dioxide(CeO_(2))through a combination of hydrothermal synthesis and ultrafast(60 s)wet impregnation approaches,utilizing H_(2)O_(2) as a facilitator(Ru/CeO_(2)-H_(2)O_(2)).Experimental characterization and density functional theory(DFT)calculation demonstrate that the created oxygen vacancy(Ov)and strong electronic interactions play crucial roles in improving catalytic activity and stability.In particular,the specific octahedral morphology and surficial-enriched Ru enhance the exposure of abundant active sites,thereby accelerating the reaction kinetics.The as-synthesized Ru/CeO_(2)-H_(2)O_(2) demonstrated commendable catalytic performance in both 1 M KOH and 1 M KOH+seawater with small overpotentials of 37 and 47 mV,respectively,to attain a current density of 10 mA cm-2.Furthermore,it exhibited remarkable long-term stability at both 10 mA cm-2 and 500 mA cm-2,and demonstrated the ability to drive overall water splitting when coupled with sustainable energy sources.Therefore,this study presents a promising approach for constructing high noble-metal utilization efficiency with a specific support,offering potential for enhanced sustainable energy applications.
基金National Natural Science Foundation of China(21871121)the 111 Project(B20027).
文摘CeO_(x)as a(co-)catalyst has been proved a promising material toward the oxygen evolution reaction(OER)in water splitting.In this study,a novel two-step method for the synthesis of cerium oxide nanoparticles in-situ generatedon CoP nanosheets toward OER is presented.Interestingly,Ce ions were gradually hydrolyzed and oxidized under the action of alkaline ligand andsolvothermal environment,and eventually existed in the form of CeO_(x)on the 2D Co-MOF nanosheets in the first step.In the followed selective phosphating process,2D Co-MOF nanosheets act as the template are transformed into CoP nanosheets but CeO_(x)is still maintained.Optimal CeO_(x)/CoP nanosheets exhibit low OER overpotential,small Tafel slope and robust durability.Furthermore,in situ electrochemical Raman spectroscopy demonstrates the transformation of the active catalytic species during the oxidation process.This in situ generation of a cocatalyst and selective phosphidation strategy provides some guidelines for the designing of highly efficient catalysts for OER and even other explorations.
基金supported by the National Natural Science Foundation of China(Grant No.51901106)the Ningbo S&T Innovation 2025 Major Special Programme(Grant No.2019B10044).
文摘Utilizing transition metal elements(Ni,Fe,Co)to design heterojunction catalysts is an effective approach for enhancing the efficiency of electrocatalytic water splitting.In this study,an n–n type junction was constructed uniformly in a CoFe-LDH@NiCoP/NF electrode through electrodeposition.This not only enhanced the conductivity and kinetic performance but also improved the electrocatalytic stability of the catalysts.The presence of an n–n type junction facilitates electron rearrangement at the heterogeneous interface,resulting in the transfer of electrons from CoFe-LDH to NiCoP.As a result,the activity of overall water splitting with CoFe-LDH@NiCoP/NF as both the cathode and anode only required 1.735 V to reach 200 mA cm^(−2);the voltage dropped by only 13 mV after 3000 CV cycles and the current density decreased by a mere 18%in 138 h at 270 mA cm^(−2).Therefore,the utilization of an n–n junction would provide more possibilities to regulate the electronic structure of electrocatalysts,especially in alkaline solutions.
基金supported by National Natural Science Foundation of China(21878130)China Postdoctoral Science Foundation(2018M642180 and 2017T110453).
文摘The development of porous metal phosphides with abundant active sites is of great importance for efficient electrocatalytic water splitting.In this work,three-dimensional(3D)-ordered mesoporous irondoped cobalt phosphide(meso-Co_(2-x)Fe_(x)P)was prepared by a nanocasting strategy using SBA-15 as the hard template combined with a subsequent phosphidation.The unique mesoporous structure of the meso-Co_(2-x)Fe_(x)P electrocatalyst resulted in the exposure of abundant active sites and favorable mass transfer for the electrocatalytic process.Due to the synergy effects of the mesoporous structure and ternary component,the meso-Co_(2-x)Fe_(x)P exhibited outstanding electrocatalytic activity with low overpotentials of 93.7 mV and 266.4 mV at a current density of 10 mA cm^(-2) for HER and OER,respectively.In addition,meso-Co_(2-x)Fe_(x)P showed excellent overall water splitting activity with an external voltage of 1.58 V at a current density of 10 mA cm^(-2),superior to the electrolytic cell consisting of 20%Pt/C and RuO_(2),demonstrating it has great potential for practical application in overall water splitting.
