摘要
通过调制脉冲电流在质子交换树脂(Nafion)粘接的无催化多孔碳电极(UCE)上电沉积Pt催化剂,对所沉积Pt催化电极性能及负载量用循环伏安法(CV)、X射线衍射仪(XRD)、透射电镜(TEM)及分光光度法进行了表征.结果表明,通过调制电沉积过程的脉冲参数,能够实现质子交换膜燃料电池(PEMFC)电极Pt催化剂的直接电化学沉积,能够调控电沉积Pt粒径,并能有效地缓解电沉积过程中析氢对沉积金属催化剂铂的干扰,所沉积的Pt催化剂利用率较传统Nafion粘接Pt/C催化电极要高.脉冲导通时间t_(on)为300μs、断通时间t_(off)为1200μs,脉冲峰值电流密度jp为100mA·cm^(-2)时,电沉积120s制得的电极的Pt晶粒约5-8nm,Pt表面利用率为43.14%,沉积Pt的电流效率为45%.
Proton exchange membrane fuel cells （PEMFC） electrodes were platinized by a modulated pulse current electrodeposition. An uncatalyzed carbon electrode （UCE）, on which a layer of Nation-bonded carbon was dispersed in advance, was served as a substrate for electrodeposition. The platinized electrode by electrodeposition was assessed by cyclic voltammetry, X-ray diffraction, transmission electron microscopy. The preliminary results showed that the height and width of deposition pulse current were critical for the properties of Pt deposit. For instance, as the on-time and off-time were fixed at 300 μs and 1200 μs, respectively, and deposition time fixed at 120 s, the electrode prepared at a peak current density of 100 mA· cm^-2 exhibited the best performance, and meanwhile the particle size of the Pt deposits was as small as 5-8 nm. The Pt utilization efficiency of such an electrode was as high as 43.14%. The current efficiency for Pt deposition, in this case, was about 45%.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2007年第4期521-525,共5页
Acta Physico-Chimica Sinica
基金
国家自然科学基金(20276066
20476109)
教育部人才支持计划(NCE/T-0850)资助项目
关键词
PEMFC
脉冲电沉积
电催化
多孔电极
PEMFC
Pulse current electrodeposition
Electro-catalysis
Porous electrode
