摘要
与电解纯水制氢相比,海水电解制氢具有更大的实际应用价值.在碱性海水中,可以通过在热力学上有利的肼氧化反应(HzOR)代替析氧反应(OER)和析氯反应(ClER)来实现节能制氢.在此,我们制备了Co掺杂的Fe-Ni_(2)P/MIL-FeCoNi异质结构阵列(FeCo-Ni_(2)P@MIL-FeCoNi).得益于异质工程和阳离子掺杂的协同作用,FeCo-Ni_(2)P@MIL-FeCoNi在碱性海水电解液中表现出优异的HzOR和析氢反应(HER)双功能电催化性能.在海水系统中的整体肼分解(OHzS)仅需要400 mV的超低电压就能达到1000 mA cm^(−2)的电流密度,且可以在500 mA cm^(−2)以上的电流密度稳定运行1000 h.作为概念验证,同样生产1.0 Nm^(3)的氢气,OHzS海水系统比无N_(2)H_(4)的整体海水分解系统(OWS)节省3.03 kW h的电力,可实现节能制氢.DFT计算表明,Co离子掺杂和构建FeCo-Ni_(2)P/MIL-FeCoNi异质界面的协同作用可以降低FeCo-Ni_(2)P@MIL-FeCoNi的水解离能垒,促进HER吸附氢和HzOR脱氢过程的热力学行为.这项工作为有效利用海洋能源领域中无限丰度的氢助力实现碳中和提供了一种实用途径.
When compared with pure water,hydrogen produced by seawater electrolysis has a better practical application potential.By replacing the oxygen evolution reaction(OER)and competitive chlorine evolution reaction(ClER)with the thermodynamically favorable anodic hydrazine oxidation reaction(HzOR)in alkaline seawater,energy-saving hydrogen production can be achieved.In this study,Fe/Co dual-doped Ni_(2)P and MIL-FeCoNi heterostructures(FeCo-Ni_(2)P@MIL-FeCoNi)arrays with simultaneous cation doping and hetero-engineering provide excellent bifunctional electrocatalytic performance for HzOR and hydrogen evolution reaction(HER)in alkaline seawater electrolyte.Overall hydrazine splitting(OHzS)in seawater is impressive,with a low cell voltage of only 400 mV required to reach 1000 mA cm^(−2)and stable operation for 1000 h to maintain above 500 mA cm^(−2).As a proof-of-concept,the OHzS system can save 3.03 kW h when producing 1.0 normal cubic meter(Nm_(3))of H_(2) when compared with the N_(2)H_(4)-free seawater system,resulting in energy-saving H_(2) production.Density functional theory calculations show that the combination of Co-doping and the fabrication of FeCo-Ni_(2)P and MIL-FeCoNi heterointerfaces can result in a low water dissociation barrier,optimized hydrogen adsorption free energy toward HER,and favorable adsorbed dehydrogenation kinetics for HzOR.This processing route paves the way for a practical approach to the efficient utilization of hydrogen,which is abundant in the ocean energy field,to achieve a carbon-neutral hydrogen economy.
作者
于青平
迟京起
刘桂杉
王宣艺
刘晓斌
李振江
邓英
王新萍
王磊
Qingping Yu;Jingqi Chi;Guishan Liu;Xuanyi Wang;Xiaobin Liu;Zhenjiang Li;Ying Deng;Xinping Wang;Lei Wang(Key Laboratory of Eco-chemical Engineering,Key Laboratory of Optic-electric Sensing and Analytical Chemistry of Life Science,Taishan Scholar Advantage and Characteristic Discipline Team of Eco Chemical Process and Technology,Qingdao University of Science and Technology,Qingdao 266042,China;College of Chemistry and Molecular Engineering,Qingdao University of Science and Technology,Qingdao 266042,China;College of Environment and Safety Engineering,Qingdao University of Science and Technology,Qingdao 266042,China;College of Chemical Engineering,Qingdao University of Science and Technology,Qingdao 266042,China;Hainan Key Laboratory of Laser Technology and Photoelectric Functional Materials,Collage of Chemistry&Chemical Engineering,Hainan Normal University,Haikou 571158,China)
基金
supported by the National Natural Science Foundation of China(51772162 and 52072197)
China Postdoctoral Science Foundation(2020M682135)
the Postdoctoral Applied Research Project of Qingdao,the Outstanding Youth Foundation of Shandong Province,China(ZR2019JQ14)
the Youth Innovation and Technology Foundation of Shandong Higher Education Institutions(2019KJC004)
the Major Scientific and Technological Innovation Project(2019JZZY020405)
the Major Basic Research Program of Natural Science Foundation of Shandong Province(ZR2020ZD09)
Taishan Scholar Young Talent Program(tsqn201909114)。
