不同pH值对直接乙醇燃料电池Pt-SnO_2/C电催化性能的影响  

Effects of Different pH Value on the Properties of Pt-SnO_2/C Electro-catalytic for the Direct Ethanol Fuel Cell

作　　者：王旭红[1] 殷仕龙[1] 马冠云[1] 阮世栋 纪网金 

机构地区：[1]常熟理工学院化学与材料工程学院,常熟215500

出　　处：《材料导报》2015年第14期11-15,35,共6页Materials Reports

摘　　要：采用水热法制备了高分散Pt-SnO2/C电催化剂,对制备工艺进行了最佳优化,考察了不同反应溶液pH值对电催化剂活性的影响。采用XRD、SEM、TEM、比表面积、粒度分析等手段对催化剂进行了结构表征。制备的Pt-SnO2纳米复合颗粒高度分散在活性炭载体表面,其平均粒径约4.5nm。通过循环伏安、计时电流、交流阻抗等技术测试了电极在乙醇体系中的电催化活性。结果表明,随着反应溶液pH值的增加,制备的Pt-SnO2/C催化剂可使乙醇的氧化发生在较低电位。在pH值为9、铂锡原子比为3∶1时,制备的Pt-SnO2/C复合催化剂,可以得到较高的乙醇氧化电催化活性和电化学长期稳定性,氧化峰电流密度高达104.54mA·cm-2。A carbon supported Pt-SnO2/C catalysts were synthesized by hydrothermal method and the prepara- tion process was well optimized. The effect of different pH of the reaction solution on ethanol oxidation reaction （EOR） of Pt-SnO2/C catalyst was evaluated. Structural and compositional analysis of the nanostructured materials were performed by EDS, XRD, TEM, BET techniques. The obtained Pt-SnO2 nanocomposite was highly dispersed on activated carbon surface with an average particle size of 4. 5 nm. The ethanol oxidation reaction was tested in a conven- tional three-electrode cell include cyclic voltammetry, chronoamperometry and AC impedance. The results show that with an increase of pH value, the as-obtained Pt-SnO2/C catalysts made ethanol oxidation occurring at lower poten- tials. At pH= 9, the Pt-SnO2/C composite catalysts with Pt/Sn atomic ratio of 3 ： 1 have higher catalytic activity for ethanol oxidation and long-term stability with electrochemical oxidation peak current density of up to 104. 54 mA· cm-2.

关 键 词：Pt-SnO2催化剂 水热法 PH值 直接乙醇燃料电池 

分 类 号：TK91[动力工程及工程热物理]