摘要
电化学分解水制氢是实现可持续、绿色制氢的重要途径,但由于阳极析氧反应(OER)缓慢的反应速率严重阻碍了全水解的效率。为从根本上解决此问题,利用低理论电位的硫离子氧化反应(SOR)取代OER,能极大的降低水电解的电压,提升水解效率,同时在阳极获得增值产物。本工作通过共沉淀法成功制备出六氰钴酸钴(CoHCC)材料,并将CoHCC负载到泡沫镍(NF)基底上制备工作电极(CoHCC/NF),作为高效的硫离子氧化反应催化剂。在三电极体系下测试其SOR催化性能,CoHCC/NF仅需要0.31 V vs.RHE的低电压就能达到100 mA·cm^(-2)的电流密度,这远优于Co(OH)_(2)/NF和NF。此外,CoHCC/NF有最低的Tafel斜率(77mA·dec^(-1))和最小的电化学阻抗,且表现出良好的稳定性。同时,在两电极体系下模拟实际电解水制氢,测试表明新型耦合反应系统(SOR-HER)在达到100 mA·cm^(-2)电流密度时所需的电压远低于传统的全水解(OER-HER)制氢系统,本工作为超低能耗制氢和硫回收提供了一条有吸引力的途径。
Electrochemical water spltting for hydrogen production is an important pathway to obtain green hydrogen.However,the slow rate of oxygen evolution reaction(OER)at the anode significantly hinders the overall efficiency of water splitting.Using the sulfion oxidation reaction(SOR)with lower theoretical potential to replace the(OER)can address this issue.This strategy can greatly reduce the voltage to enhance the efficiency of water splitting and obtain value-added products.In this work,cobalt hexacyanocobaltate(CoHCC)was successfully prepared by the co-precipitation method,which was coated on a nickel foam substrate to prepare the working electrode as an efficient catalyst for the SOR.The SOR catalytic performance of CoHCC was tested in a three-electrode system.CoHCC/NF only requires O.31 V vs.RHE to achieve a current density of 100 mA·cm^(-2),which is much superior to those of Co(OH)_(2)/NF and NF.Furthermore,CoHCC/NF also showed the lowest Tafel slope(77 mV:dec^(-1))and the smallest electrochemical impedance,and good catalytic stability.Meanwhile,the novel coupled system(SOR-HER)required a significantly lower voltage to achieve a current density of 100 mA·cm^(-2) compared to the traditional overall water spliting(OER-HER)system of hydrogen production.This work offers an attractive approach for ultra-low energy consumption hydrogen production and sulfur recovery.
作者
郭汝成
董斌
刘崇菠
冯翔瑞
安琪
赵虔
高涛涛
GUO Ru-cheng;DONG Bin;LIU Chong-bo;FENG Xiang-rui;AN Qi;ZHAO Qian;GAO Tao-tao(School of Mechanical Engineering,Chengdu University,Chengdu 610106,China;Institute for Advanced Study,Chengdu University,Chengdu 610106,China)
出处
《化学研究与应用》
北大核心
2025年第8期2395-2400,共6页
Chemical Research and Application
关键词
电解水
电化学制氢
硫离子氧化反应
六氰钴酸钴
耦合反应
water electrolysis
electrochemical hydrogen production
sulfion oxidation reaction
cobalt hexacyanocobaltate
coupled reaction
