纳米Pt/Graphene复合电极的制备及对甲醇电催化性能的影响

采用一步还原法制备直接甲醇燃料电池纳米Pt/graphene (Pt/G)阳极. XRD和SEM表征表明Pt纳米均匀分散于石墨烯表面.循环伏安和计时电流的电化学测定结果表明:复合纳米Pt/G的催化活性和稳定性优于纯铂;采用计时电量法测定298 K时甲醇在硫酸溶液中扩散系数为1.37×10-9 cm2·s-1,以及在不同阶跃电位下甲醇催化氧化反应速率常数k_f. 

Pt/Graphene Nanocomposite Preparation and its Electrocatalytic Performance for Methanol Oxidation

The Pt/graphene (Pt/G) nanocomposite was prepared via a facile and clean one-step chemical reduction method. The obtained catalysts were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), which directly show that Pt nanoparticles (NPs) successfully assembled on grapheme and well distributed on the grapheme sheets. The further electrocatalytic characterization of the catalysts for methanol oxidation reaction (MOR) including cyclic voltammetry (CV) and chronoamperometry (CA) indicated that Pt/graphene has significantly higher electrocatalytic activity and stability for MOR compared to Pt. Chronocoulometry was used by controlling step potential to determine the diffusion coefficient of methanol in sulfuric acid which was 1.37×10^-9 cm²·s^-1 at 298 K, as well as the forward rate constants (k_f) at different potentials.