集成有CNTs和Ni-Ni(OH)_(2)异质结构的电解析氢自支撑薄膜催化剂  

Self-supported film catalyst integrated with multifunctional carbon nanotubes and Ni-Ni(OH)_(2)heterostructure for promoted hydrogen evolution

作　　者：赵万成 马加朋 田栋[1] 康宝涛 夏方诠[1] 成婧 吴亚军 王梦遥 武刚 Wancheng Zhao;Jiapeng Ma;Dong Tian;Baotao Kang;Fangquan Xia;Jing Cheng;Yajun Wu;Mengyao Wang;Gang Wu(School of Chemistry and Chemical Engineering,University of Jinan,Jinan 250022,Shandong,China;Department of Chemical and Biological Engineering,University at Buffalo,The State University of New York,Buffalo,NY 14260,United States)

机构地区：[1]济南大学化学化工学院,山东济南250022 [2]纽约州立大学布法罗分校化学与生物工程系,纽约,美国

出　　处：《Chinese Journal of Catalysis》2024年第7期287-295,共9页催化学报（英文）

摘　　要：氢气是一种重要的能量储存载体.通过电解水析氢的方式,可以将其他可再生能源转化为电能,并以化学能的形式储存于氢气中.为了提高电解析氢过程的能量转化效率、降低能耗,需要高活性的析氢催化剂.这些催化剂不仅应具有巨大的比表面积,还应具备适中的氢吸附能和较强的解离水的能力.铂基催化剂在电解析氢方面展现出了显著的优势,而同族的镍基催化剂因其高性价比而备受关注.然而,在电解析氢过程中,镍基催化剂存在氢吸附强度高和解离水能力弱两个重要缺陷,这导致析氢过程动力学不理想.因此,本文的研究思路是探索如何在镍基催化剂中引入功能性组分,以平衡氢吸附能和催化水解离的能力,从而实现析氢性能的提升.研究表明,碳纳米管(CNTs)可以改善催化剂的电解析氢性能,而Ni(OH)_(2)则可以提升催化剂解离水的能力.因此,本文采用复合电沉积法制得CNTs-Ni薄膜,并通过原位氧化在其表面形成Ni-Ni(OH)_(2)异质结构,构建了包含CNTs和Ni-Ni(OH)_(2)两种功能组分的CNTs-Ni-Ni(OH)_(2)薄膜.该薄膜展现出与Pt/C相当的析氢活性和更出色的稳定性.微观形貌分析显示,CNTs的引入使CNTs-Ni薄膜具有复杂的三维结构,镍以高度褶皱的微球形态均匀负载在CNTs表面,形成巨大的比表面积.电化学测试和模拟计算结果证实,CNTs-Ni薄膜的析氢活性较纯镍有显著提高,这归因于其巨大的电化学活性面积以及CNTs对析氢过程动力学的积极影响.当优化沉积时间和CNTs表面镍的负载量时,CNTs-Ni薄膜的电化学活性面积和析氢活性均得到显著提升.进一步氧化处理后,通过X射线光电子能谱和X射线衍射等测试手段证实了Ni-Ni(OH)_(2)异质结构的形成,并观察到电化学活性面积的增大和析氢活性的改善.此外,深入研究发现,随着氧化时间的延长,单位电化学活性面积上的析氢活性出现下降.结合析氢过程的背�In order to reduce energy consumption in water electrolysis,it is of great importance to design active and stable electrocatalysts for hydrogen evolution reaction(HER)in alkaline solution,especially based on earth-abundant metal.Here we integrate carbon nanotubes(CNTs)and Ni-Ni(OH)_(2)heterostructure multifunctional components to design a self-supported 3D CNTs-Ni-Ni(OH)_(2)catalyst for HER by composite deposition and subsequent in-situ oxidation.In alkaline solution,this designed CNTs-Ni-Ni(OH)_(2)catalyst exhibits 0 mV onset overpotential,and overpotentials of 65 mV and 109 mV at 10 and 50 mA/cm^(2)respectively.Electrochemical measurements,characterizations,and simulation results attribute the outstanding performance to the incorporation of CNTs and heterostructure.CNTs induce the formation 3D catalytic surface,enhance electrochemical active surface area,and more importantly weaken the adsorption of H.Moreover,the formation of heterostructure,especially reversible Ni(OH)_(2),supplies active sites and adjusts the adsorption strength of H atom to an optimal value.CNTs and heterostructure synergistically facilitate water adsorption,promote water dissociation,and accelerate H_(2)desorption.Significantly,integration of multifunctional components supplies a distinct strategy for development of cost-effective electrocatalyst with outstanding performance.

关 键 词：Ni-Ni(OH)_(2)异质结构 电解催化剂 析氢反应 碳纳米管 吸附自由能 

分 类 号：TQ116.2[化学工程—无机化工] TQ426