苯电催化加氢SPE电极的制备研究

PREPARATION OF SPE ELECTRODE FOR ELECTROCATLYTIC HYDROGENATION OF BENZENE

研究了在离子交换膜上用化学沉积和浸渍还原制备SPE电极Pt/Nafion的方法,利用SEM和荧光显微镜对Pt在膜上的形态进行了研究,并以交换电流密度为指标,评价电极苯加氢性能。研究结果表明:用化学沉积法制备的电极载铂量较大,交换电流密度较小,铂颗粒堆积密集,且主要分布在膜的外侧;而用浸渍还原法制备的电极载铂量较小,交换电流密度较大,铂颗粒主要分布在膜的内侧;因此确定采用浸渍还原法制备SPE电极。浸渍还原法的优化条件为:Pt(NH3)4Cl2浓度0.8mmol/L,浸渍时间40min,NaBH4浓度1.2mmol/L,还原时间2h,反应温度50℃,

Chemical deposition and impregnation-reduction to platinize the surface of polymer electrolyte membrane to form SPE electrode have been studied for electrocatalytic hydrogenation of benzene. The scanning electron and fluorescence microscope were used to investigate the morphology of platinum on the membrane. The catalytic performance of electrode was evaluated by the electrocatalytic reaction of hydrogenation of benzene. The electrode prepared using chemical deposition has low current exchange density and high deposition of platinum, which is mainly deposited on the outside of the membrane＇ s surface. In contrast, the electrode using impregnation-reduction （I-R） has high current exchange density and low deposition of platinum, which are micro-granules deposited on the inside of the membrane＇ s surface. The optimal preparation parameters of Pt/Nafion electrode by I-R as follows： Pt（ NH3 ）4Cl2 concentration 0.8mmol/L, impregnate time 40min, NaBH4 concentration 1.2mmol/L, reduction time 2h, reaction temperature 50℃, and stir speed 300r/min.