摘要
过渡金属氢氧化物中,氢氧化镍(Ni(OH)_2)以其高电化学活性、低成本、环境友好等特点受到人们的关注~([1])。Ni(OH)_2已被广泛用作超级电容器材料,但作为氧气还原(ORR)催化剂的报道还较少~([2,3])。本研究采用一种简便、绿色的恒电位共沉积法合成氢氧化镍/聚酰胺-胺功能化石墨烯(Ni(OH)_2/PAMAM-RGO)复合物,并研究了其在碱性介质中ORR催化性能,得到了如下结论:(1)Ni(OH)_2/PAMAM-RGO复合催化剂的形成源于PAMAM与GO的成键及与Ni~(2+)的配位作用(Fig.1);(2)与同样条件下制备的Ni(OH)_2、PAMAM-RGO相比,Ni(OH)_2/PAMAM-RGO显示出最高的ORR活性,初始电位为0.83 V vs.RHE,分别比Ni(OH)_2、PAMAM-RGO正移了110和60 mV(Fig.2);(3)Ni(OH)_2/PAMAM-RGO复合物在催化ORR时表现出优越的催化稳定性(Fig.3),其优良的稳定性可能归因于Ni~(2+)与PAMAM上的胺基、亚胺基配位作用。
Nickel hydroxide(Ni(OH)_2) has received special attention because it is highly active, inexpensive, and environment friendly~([1]). Although these oxide materials have been well-exploited for supercapacitors, there are few papers on their electrocatalytic activity towards ORR~([2,3]). Herein we report a novel Ni(OH)_2/PAMAM-RGO composite via cathodic deposition and the composite exhibits enhanced electrocatalytic ORR performance.
引文
[1]Feng L.;Zhu Y.;Ding H.;Ni C.Journal of Power Sources.2014,267:430.
[2]Farjami E.;Rottmayer M.A.;Deiner L.J.Journal of Materials Chemistry A.2013,1:15501.
[3]Farjami E.;Deiner L.J.Journal of the Electrochemical Society,2015,162:H571.