PtAu插层类水滑石对甲醇的电催化氧化

为提高直接甲醇燃料电池阳极催化剂抗CO中毒性能,降低成本,实现其大规模商业化,通过浸渍法和电化学还原法制备了一种新型PtAu纳米双金属催化剂,利用循环伏安扫描,交流阻抗测及计时电流测试研究不同摩尔比的PtAu插层水滑石材料对甲醇氧化的电催化性能。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、BET比表面积对催化剂的晶体结构,形貌等进行表征。结果表明,4种不同摩尔比的PtxAuy/MgAl-LDH催化剂均具有良好的层状结构特征,且BET比表面积均比商业型镁铝水滑石大。其中,Pt1Au0.5/MgAl-LDH催化剂对甲醇的电催化氧化具有最高的电流密度和最小的电荷转移阻力,且表现出了良好的抗CO中毒性能及稳定性。

Electrocatalytic Oxidation of Methanol by PtAu Intercalated Hydrotalcite

In order to improve anti-CO poisoning performance of direct methanol fuel cell anode catalyst, to reduce the cost, and to implement its large-scale commercialization, a new type of PtAu nano-bimetallic catalyst was prepared by dipping and electrochemical reduction method. Cyclic voltammetric scanning, AC impedance measurement and chronoamperometry were used to study electrocatalytic performance of PtAu intercalated hydrotalcite materials with different molar ratios for methanol oxidation. Crystal structure and morphology of the catalyst were characterized by X-ray diffractometry(XRD), scanning electron microscopy(SEM) and BET specific surface area. The results showed that four PtxAuy/MgAl-LDH catalysts with different molar ratios had good layered structure, and BET specific surface area was larger than commercial magnesium-aluminum hydrotalcite. The Pt1Au0.5/MgAl-LDH catalyst had the highest current density and the lowest charge transfer resistance for methanol electrocatalytic oxidation, and exhibited good resistance to CO poisoning performance and stability.