Seawater battery is an advanced energy storage system that enables conversion of chemical energy to electricity by consuming metals,dissolved oxygen and seawater in anode,cathode and electrolyte,respectively.However,t...Seawater battery is an advanced energy storage system that enables conversion of chemical energy to electricity by consuming metals,dissolved oxygen and seawater in anode,cathode and electrolyte,respectively.However,the oxygen reduction reaction(ORR)activity and stability of electrocatalysts can be easily deactivated due to the severe Cl~-permeation and corrosion in seawater electrolyte.Herein,we developed a structural buffer engineering strategy by spontaneously anchoring Cl~-intoα-Co(OH)_(2) as efficient and stable ORR electrocatalysts,in which the ultrathinα-Co(OH)_(2) nanosheets were synthesized using an ultrafast solution high-temperature shock(SHTS)strategy.The large lattice space(~0.8 nm)of layeredα-Co(OH)_(2) ensured the spontaneously penetration of Cl~-into the lattice structure and replaced part of OH~-to formα-Co(OH)_(2-x)Cl_x.The continuous leaching and compensating of saturated Cl inα-Co(OH)_(2-x)Cl_x could enhance the Cl~-corrosion resistance and modulate electronic structure of Co metallic sites,thus improving the ORR electrocatalytic activity and stability in seawater electrolyte.Theα-Co(OH)_(2-x)Cl_x seawater batteries display superior onset and half-wave potentials of 0.71 and 0.66 V,respectively,which are much better than the counterparts ofα-Co(OH)_(2) and ofβ-Co(OH)_(2) with no Cl~-penetrating and no buffer structure.Theα-Co(OH)_(2-x)Cl_x-based seawater batteries display stable open-circuit potential of 1.69 V and outstanding specific capacity of 1345 mAh·g^(-1).展开更多
Constructing heterointerface engineering has becoming an effective and general strategy for developing highly efficient and durable nonnoble electrocatalysts for catalyzing both hydrogen evolution reaction(HER)and oxy...Constructing heterointerface engineering has becoming an effective and general strategy for developing highly efficient and durable nonnoble electrocatalysts for catalyzing both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).In this work,we synthesized a self-supporting heterogeneous NiSe@Co_(0.85)Se/NF electrocatalyst using a facile in situ selenization of transition metal precursors that coated on the nickel foam(NF)in polyol solution.The NF was used as both conductive substrate and nickel source,ensuring superior electronic conductivity for catalyzing.The NiSe@-Co_(0.85)Se/NF exhibited remarkable bifunctional electrocatalytic activities with HER overpotential of 168 mV and OER overpotential of 258 mV to achieve 10 mA·cm-2.The water splitting system using NiSe@Co_(0.85)Se/NF as both anode and cathode electrodes achieved a current density of 10 mA·cm^(-2) at 1.61 V with nearly 100% faradaic efficiency and impressively long-term stability.The efficient bifunctional catalytic performance of NiSe@-Co_(0.85)Se/NF should be attributed to the electronic modulation and synergistic effect between NiSe and Co_(0.85)Se,the intrinsic metallic conductivity and the enlarged active sites exposure.This work provides a facile method for developing heterogeneous bifunctional catalysts for advanced electrochemical energy conversion technologies.展开更多
基金financially supported by the Key Research and Development Project of Hainan Province(No.ZDYF2022GXJS006)the National Natural Science Foundation of China(Nos.52177220 and 52231008)。
文摘Seawater battery is an advanced energy storage system that enables conversion of chemical energy to electricity by consuming metals,dissolved oxygen and seawater in anode,cathode and electrolyte,respectively.However,the oxygen reduction reaction(ORR)activity and stability of electrocatalysts can be easily deactivated due to the severe Cl~-permeation and corrosion in seawater electrolyte.Herein,we developed a structural buffer engineering strategy by spontaneously anchoring Cl~-intoα-Co(OH)_(2) as efficient and stable ORR electrocatalysts,in which the ultrathinα-Co(OH)_(2) nanosheets were synthesized using an ultrafast solution high-temperature shock(SHTS)strategy.The large lattice space(~0.8 nm)of layeredα-Co(OH)_(2) ensured the spontaneously penetration of Cl~-into the lattice structure and replaced part of OH~-to formα-Co(OH)_(2-x)Cl_x.The continuous leaching and compensating of saturated Cl inα-Co(OH)_(2-x)Cl_x could enhance the Cl~-corrosion resistance and modulate electronic structure of Co metallic sites,thus improving the ORR electrocatalytic activity and stability in seawater electrolyte.Theα-Co(OH)_(2-x)Cl_x seawater batteries display superior onset and half-wave potentials of 0.71 and 0.66 V,respectively,which are much better than the counterparts ofα-Co(OH)_(2) and ofβ-Co(OH)_(2) with no Cl~-penetrating and no buffer structure.Theα-Co(OH)_(2-x)Cl_x-based seawater batteries display stable open-circuit potential of 1.69 V and outstanding specific capacity of 1345 mAh·g^(-1).
基金financially supported by the National Natural Science Foundation of China(No.51804216)。
文摘Constructing heterointerface engineering has becoming an effective and general strategy for developing highly efficient and durable nonnoble electrocatalysts for catalyzing both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).In this work,we synthesized a self-supporting heterogeneous NiSe@Co_(0.85)Se/NF electrocatalyst using a facile in situ selenization of transition metal precursors that coated on the nickel foam(NF)in polyol solution.The NF was used as both conductive substrate and nickel source,ensuring superior electronic conductivity for catalyzing.The NiSe@-Co_(0.85)Se/NF exhibited remarkable bifunctional electrocatalytic activities with HER overpotential of 168 mV and OER overpotential of 258 mV to achieve 10 mA·cm-2.The water splitting system using NiSe@Co_(0.85)Se/NF as both anode and cathode electrodes achieved a current density of 10 mA·cm^(-2) at 1.61 V with nearly 100% faradaic efficiency and impressively long-term stability.The efficient bifunctional catalytic performance of NiSe@-Co_(0.85)Se/NF should be attributed to the electronic modulation and synergistic effect between NiSe and Co_(0.85)Se,the intrinsic metallic conductivity and the enlarged active sites exposure.This work provides a facile method for developing heterogeneous bifunctional catalysts for advanced electrochemical energy conversion technologies.
