Pt掺杂的纳米Ni电催化氧化甲醇性能的研究

Performance of Nano-Ni Doped with Pt for Methanol Electro-catalytic Oxidation

摘要:

采用溶胶凝胶法制备了碳载纳米双金属Ni-Pt (5%，质量分数)/C电催化剂，用TEM、XRD和XPS表征金属粒子的形貌、晶相结构、表面元素及其价态，循环伏安法测试催化剂在碱性溶液中电催化氧化甲醇的活性。结果表明，Ni-Pt金属粒子在碳载体上分布均匀，粒径为3~6 nm，少量Pt的掺杂对纳米Ni活性有明显提高，其中，合金型Ni-Pt (5%)/C在1.0 mol/L NaOH＋1.0 mol/L CH3OH溶液中峰电流密度可达85.6 mA/mg，是Ni/C峰电流密度的8.7倍，达到Pt/C峰电流密度的15.3%。单位质量铂的电流显著提高。

Abstract:

Carbon supported nano-nickel-platinum electrocatalyst samples of Ni-Pt (5wt%)/C were prepared by the colloidal-gelatin method. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to evaluate the metal particles’ morphology, crystal configuration, superficial element constitution and value. Moreover, cyclic voltammeter was employed to measure the catalytic activity for the electro-catalytic oxidation of methanol in an alkaline medium. The results show that Ni-Pt particles are distributed homogeneously on the carbon, with the particle sizes of 3-6 nm; the Pt doping improves largely the activity of Ni nano-particles, and the peak current density of alloy Ni-Pt(5wt%)/C catalyst reaches 85.6 mA/mg in the solution of 1.0 mol/L NaOH + 1.0 mol/L CH3OH, which is 8.7 times of that of Ni/C, and 15.3% of that of Pt/C. The current of Pt per unit mass is increased obviously.