摘要
与脉冲电沉积及恒流电沉积法相比,恒电位电沉积制备的电催化剂具有更优异的性能,目前很少用此法制备质子交换膜燃料电池用Pt-Ni合金催化剂。采用电化学还原法在多孔碳布及玻碳电极表面恒电位电沉积Pt-Ni合金催化剂。用X射线衍射(XRD)、能量色散谱(EDS)和扫描电镜(SEM)等对Pt-Ni合金催化剂的微观结构、组分和形貌进行了表征,并用循环伏安(CV)曲线评价了其电催化活性。研究了电沉积参数(沉积电位、电解液温度和沉积时间)对Pt-Ni合金催化剂的微观结构和电催化活性的影响。结果表明:沉积电位影响合金催化剂形核速度,引起微观结构不同,电解液温度影响着催化剂的成核和生长,沉积时间影响着Pt-Ni合金的沉积量;沉积电位为-0.35 V,电解液温度为50℃,沉积时间为15 min时,Pt-Ni合金催化剂均匀地分散于碳载体表面,粒径大约为11.9 nm,具有最大的电化学活性表面积(EASA),达44.19 m2/g,电催化活性最好。
Pt-Ni alloy catalyst was prepared on the surfaces of porous carbon cloth and glassy carbon electrode via potentiostatic electrodeposition in association with electrochemical reduction.The microstructure,composition and morphology of as-prepared Pt-Ni alloy catalyst were characterized by X-ray diffraction,energy dispersive spectromctry and scanning electron microscopy.The electrocalalytie activities of as-prepared Pt-Ni catalyst were measured by cyclic voltammetry;and the effects of electrodeposition parameters(potential,temperature of electrolyte,and electrodeposition time)on the microstructure and electrocatalytic activities of Pt-Ni catalyst were investigated.Results showed that the electrodeposition potential affected the electrochemical nucleation rate thereby leading to differences in the microstructure of the Pt-Ni catalyst,The temperature of electrolyte influenced the nucleation and growth of the catalyst,and the electrodepositon time affected the amount of electrodeposited Pt-Ni catalyst.Particularly,the Pt-Ni catalyst obtained at a potential of-0.35 V,an electrolyte temperature of50℃,and an electrodeposition time of 15 min had a particle size of 11.9 nm and was uniformly distributed on the surface of the carbon support,and it exhibited the maximum electrochemical active surface area of 44.19 m^2/g as well as the best electrocatalytic performance.
出处
《材料保护》
CAS
CSCD
北大核心
2014年第8期43-45,58,共4页
Materials Protection
基金
江苏高校优势学科建设工程资助项目(SKL200608SIC)
关键词
恒电位沉积
Pt-Ni合金
催化剂
电催化活性
沉积电位
电解液温度
沉积时间
potcntiostatic electrodeposition
Pt-Ni alloy
catalyst
electrocatalytic activities
electrodeposition potential
temperature of electrolyte
electrodeposition time
