新型炭材料Issue(3)：231-235,5.
不同pH值下Pt-Sn/石墨烯复合材料的电催化性能
Preparation of Pt-Sn/graphene catalysts and their activities for ethanol electrooxidation in polyol synthesis
摘要
Abstract
Pt-Sn/graphene catalysts were prepared by heat treatment of a dispersion of graphene oxide, SnCl2 and H2 PtCl6 in eth-ylene glycol at 130℃ for 3 h after its pH value had been adjusted to 12 by NaOH, followed by centrifuging, washing with ethanol and water, and cryodrying. The pH value of the heat-treated dispersion was controlled by adding dilute nitric acid to 2, 4 and 6 to mediate the properties of the catalysts and its effects on the compositions, microstructure and catalytic activities of the resulting cata-lysts in ethanol electrooxidation. These were investigated by XRD, ICP, TEM and cyclic voltammetry. Results indicated that with decreasing pH values the Sn content increased, the Pt/Sn atom ratio decreased and the electrochemical activity increased. The cur-rent density for ethanol electrooxidation was increased by 120% at the pH value of 2 compared for the sample without nitric acid. The improvement of the catalytic activity can be ascribed to an increased loading of Sn and Pt since the oxidative product of ethylene glycol in the heat treatment acted as a chelating agent for metal nanoparticles under high pH values. A very simple acid-treatment-as-sisted polyol route to prepare graphene supported Pt-Sn nanoparticles were developed. To evaluate the composition, microstructure and electrochemical activity of catalysts treated with different pH values of acid solution have been characterized by XRD、ICP、TEM and cyclic voltammetry. And the changes of Pt and Sn metal particles loading on the surface of graphene were discussed. The results show that graphene is a good support. With the increase of pH values, the Sn content of catalysts increased and the electrochemical activity was improved. As the pH values of acid solution was decreased to 2, the synergistic effect of Pt and Sn reached its maxi-mum, and the current densities of ethanol electrooxidation with the catalysts were about 120% higher than that of original Pt-Sn/G catalysts, which also reached the maximum.关键词
Pt-Sn/石墨烯/pH值/电催化性能/协同效应Key words
Pt-Sn/graphene/pH values/Electric-catalytic properties/Synergistic effect分类
通用工业技术引用本文复制引用
王永祯,王勇..不同pH值下Pt-Sn/石墨烯复合材料的电催化性能[J].新型炭材料,2014,(3):231-235,5.基金项目
国家自然科学基金(51172152,51242007) （51172152,51242007）
山西省工业科技攻关项目(20130322005-05).@@@@National Natural Science Foundation of China (51172152,51242007) （20130322005-05）
Shanxi Province Science and Technology Fund (20130322005-05) （20130322005-05）
