关键词: 纳米纤维聚苯胺, 电沉积Pt颗粒, 甲醇氧化, 电化学催化

Abstract: Nano-fibular polyaniline(PANI) film with large specific surface area was prepared by pulse galvanostatic method(PGM) and the electrode of nano-fibular PANI modified by Pt microparticles[Pt/(nano-fibular PANI)] was used as the catalyzed electrode for methanol oxidation in this paper. The research results show that there is a synergism for methanol oxidation on Pt/(nano-fibular PANI) electrode. The Pt/(nano-fibular PANI) electrode exhibits a considerably higher electrocatalytic activity on methanol oxidation than that of the Pt/(granular PANI) electrode when Pt is deposited by cyclic voltammetry method (CVM). The catalytic activity of Pt/(nano-fibular PANI) electrode is 8 times higher than that of Pt/(granular PANI) electrode under the condition of Pt loading of 800 μg•cm－2. Moreover, the research results show that the catalytic activity of Pt/PANI electrode can be further improved when Pt is deposited by PGM. The results of scanning electron microscopy (SEM) show that a large number of Pt microparticles with diameter of about 30 nm are dispersed homogeneously on nano-fibular PANI with diameter about 100 nm. This leads to an increase in specific surface area and dispersion of Pt and hence results in a high catalytic activity of the Pt/PANI composite electrode. The results of electrochemical impedance spectroscopy (EIS) show that the Pt/(nano-fibular PANI) electrode has relatively lower electrochemical impedance for methanol oxidation than that of the Pt/(granular PANI) electrode.

Key words: Nano-fibular polyaniline, Electrodepositing Pt microparticles, 　Methanol oxidation, Electrocatalysis