在碳纸(CP)及涂覆了碳粉科琴黑fKB)或石墨烯纳米片(GNs)的碳纸上,原位电沉积了AuPt合金,制备成CP/AuPt、CP/KB/AuPt、CP/GNs/AuPt三种空气电极。对比研究发现。以石墨烯纳米片为载体的CP/GNs/AuPt空气电极上.AuPt合金载量高.颗粒分散均匀,粒径约为100nm,Au和Pt的含量分别为78.84%(n/n)和21.16%(n/n)。在O.1mol.L^-1 KOH溶液中氧还原反应的起峰电势为0.93V,催化活性和稳定性优于其他两种空气电极。分析认为,石墨烯纳米片具有高导电性、高比表面积以及较多的缺陷活性位点.有利于AuPt合金在其上均匀电沉积且沉积载量较高.同时GNs本身具有一定的催化活性,两者能够产生协同催化作用.提高了CP/GNs/AuPt电极的催化性能。
Ketjen black (KB) or graphene nanosheets (GNs) were supported on carbon paper (CP) firstly. Subseq- uently, in order to prepare air electrodes, AuPt alloys were electrodeposited on CP, CP/KB, CP/GNs substrates. It is found that the AuPt alloy particles are dispersed uniformly on the CP/GNs/AuPt air electrode, meanwhile the particle size is about 100 nm. The load mass of AuPt alloy catalyst was higher than others electrodes, meanwhile, the test of EDS exhibits that Au content and Pt content are 78.84%(n/n) and 21.16%(n/n), respectively. With a scan speed of 1 mV. s^-1, the onset potential of linear sweep voltammograms (LSV) for oxygen reduction reaction (ORR) is 0.93 V in 0.1 mol.L^-1 KOH solution. The CP/GNs/AuPt air electrode exhibit enhanced electrocatalytic activity and stability for ORR in comparison with the CP/AuPt and CP/KB/AuPt electrodes, which is mainly attributed to the high conductivity, large specific surface area of the GNs. GNs facilitate the uniform electrodeposition and increase the load mass of AuPt alloy. Since GNs has some catalytic activity, the synergistic effect between the GNs and AuPt alloy particles improves the catalytic performance of the CP/GNs/AuPt electrode.