Cu-induced interface engineering of NiCu/Ni_(3)N heterostructures for enhanced alkaline hydrogen oxidation reaction  

构建NiCu/Ni_(3)N异质结构催化剂以实现碱性条件下高效氢氧化反应

作　　者：Jinchi Li Wanhai Zhou Shuqi Yu Chen Qing Jian He Liang Zeng Yao Wang Yungui Chen 李金池;周万海;于书棋;卿晨;何剑;曾亮;王尧;陈云贵(四川大学新能源与低碳技术研究院,四川成都610065;复旦大学化学与材料学院,先进材料实验室,上海200433;四川大学材料科学与工程学院,新能源材料系,四川成都610065;四川大学新能源材料与器件教育部工程研究中心,四川成都610065)

机构地区：[1]Institute of New Energy and Low-Carbon Technology,Sichuan University,Chengdu 610065,Sichuan,China [2]Laboratory of Advanced Materials,College of Chemistry and Materials,Fudan University,Shanghai 200433,China [3]Department of Advanced Energy Materials,College of Materials Science and Engineering,Sichuan University,Chengdu 610065,Sichuan,China [4]Engineering Research Center of Alternative Energy Materials&Devices,Ministry of Education,Chengdu 610065,Sichuan,China

出　　处：《Chinese Journal of Catalysis》2024年第12期186-193,共8页催化学报(英文)

基　　金：国家自然科学基金(22279082).

摘　　要：Constructing well-defined interfaces in catalysts is a highly effective method to accelerate reactions with multiple intermediates.In this study,we developed a heterostructure catalyst combining fcc NiCu and hcp Ni_(3)N,aiming at achieving superior performance in alkaline hydrogen electrocatalysis.The NiCu/Ni_(3)N not only overcomes the inadequate hydroxyl binding energy performance of NiCu alloys but also solves the problems of insufficient active sites found in most Ni/Ni_(3)N.Experimental results and density functional theoretical calculations reveal that the formation of heterostructure significantly depends on the amount of Cu.This approach effectively prevents the side effects of increased catalyst particle size,typically resulting from the high temperatures and prolonged reaction times required for conventional synthesis of Ni/Ni_(3)N.The interface of this heterostructure induces a distinctive overlapping effect that enhances the adsorption of water and lowers the energy barrier for the rate-determining step.The NiCu/Ni_(3)N catalyst shows an impressive activity of 71.8 mA mg^(-1) at an overpotential of 50 mV,a 14.7 times efficiency enhancement compared to pure Ni and comparable to that of low-loaded commercial Pt/C.This research highlights the potential of NiCu/Ni_(3)N in advancing catalyst development.能源存储与转换装置在便携式电源、电动汽车和大规模能源存储等领域中扮演着至关重要的角色.其中,阴离子交换膜燃料电池(AEMFCs)因其高能量效率和可持续性,逐渐成为可再生能源集成的理想选择.AEMFCs的优势在于可以在较低温度下操作,同时具备较高的能量转化效率.然而,在实际应用中AEMFCs的性能仍主要依赖于贵金属催化剂,如铂和铑.这些贵金属催化剂虽然表现出优异的催化性能,但其昂贵的成本限制了AEMFCs的大规模应用.因此,开发高效的非贵金属氢氧化反应(HOR)催化剂成为提高AEMFCs性能和降低成本的关键.本文成功制备了NiCu/Ni_(3)N异质结构催化剂,结合了NiCu合金和Ni_(3)N的协同优势,显著优化了氢吸附能(HBE)和羟基吸附能(OHBE),从而大幅度提高了HOR的催化活性.不同于传统的通过调控焙烧条件来制备催化剂的方法,本文采用调控Cu的掺杂含量实现异质结构的构建.该方法不仅克服了传统方法的限制,还为催化剂设计提供了新的思路.研究发现,当Cu掺杂量过多时,会对Ni_(3)N的形成产生抑制作用,导致Ni_(3)N仅在富Ni区域生成.这种掺杂导致了在NiCu合金表面形成了平均粒径约为5 nm的小尺寸Ni_(3)N颗粒.X射线衍射、透射电子显微镜、X射线光电子能谱以及X射线吸收精细结构等表征结果证实了NiCu/Ni_(3)N异质结构成功合成.电化学测试结果表明,NiCu/Ni_(3)N催化剂在0.1 mol L^(-1) KOH溶液中的氢氧化反应表现出较好的催化活性,在50 mV的质量活性高达71.8 mA mg^(-1),明显高于纯Ni和NiCu合金催化剂.同时,该催化剂的交换电流密度也显著提高,表明其本征催化活性得到了显著增强.稳定性测试结果显示,该催化剂在经过1000次循环后,其催化活性几乎没有衰减,展现出较好的稳定性,说明具有较强的实际应用性能.为了深入理解催化性能的提升机制,进行了密度泛函理论计算,结果表明,NiCu/Ni_(3)N�

关 键 词：Hydrogen oxidation reaction Heterostructured electrocatalyst Non-precious metal catalyst Hydrogen adsorption energy Hydroxyl adsorption energy 

分 类 号：O64[理学—物理化学]