摘要
实验表明 ,铂黑粉末 /Nafion复合微电极的析氢超电势比同样面积的平面铂复合微电极为低 .这是由于Nafion膜与平面铂电极或者铂黑粉末形成的Pt/Nation界面之外还存在可供反应中间物扩散及进行复合反应的自由铂表面 ,这些扩散和复合反应降低了Pt/Nafion界面上电化学反应中间物浓度 ,从而降低了氢超电势 ,加速了析氢反应的速度 .
The decrease of over_potential of hydrogen evolution reaction at Pt black powder/Nafion microelectrode, comparing that of the Pt microdisk/Nafion electrode, was evident from the polarization curves of the Pt microdisk/Nafion electrode, platinized Pt micrdisk/Nafion electrode and Pt black powder/Nafion microelectrode. It is also evidenced by a plane Pt electrode with an additional free Pt surface. The surface diffusion and the surface recombination reaction of the adsorbed intermediate at the free surface of the Pt particles were supposed. It is an additional reaction path that induced the decrease of the concentration of the adsorbed intermediate. Thereby, the over_potential decreased.
出处
《电化学》
CAS
CSCD
2000年第2期181-186,共6页
Journal of Electrochemistry
基金
国家自然科学基金!资助课题 (2 98730 35 )
关键词
表面扩散
吸咐中间物
氢析出
超电势
铂电极
Surface diffusion, Adsorbed intermediate, Hydrogen evolution reaction, Over_potential
