石墨烯/Sr2Ni0.4Co1.6O6复合材料的制备及其性能

Preparation and Properties of Graphene/ Sr2Ni0.4Co1.6O6 Composites

摘要:

通过溶胶-凝胶法合成双钙钛矿型氧化物Sr2Ni0.4Co1.6O6，通过改性Hummers还原方法制备出薄层石墨烯，并制备单一物质和两者复合材料的双功能氧电极，用于测试其氧催化性能。XRD、EDS、SEM、红外光谱表征得出，Sr2Ni0.4Co1.6O6均匀的分布于薄层石墨烯片层表面。电化学性能测试表明，单一Sr2Ni0.4Co1.6O6和薄层石墨烯的氧还原反应(ORR)最大电流密度分别为183.0 mA/cm2、151.6 mA/cm2 (-0.6 V vs Hg/HgO)，氧析出反应(OER)最大电流密度为267.7 mA/cm2、117.4 mA/cm2 (1 V vs Hg/HgO)。当薄层石墨烯添加量占复合催化剂重量比10 %时，复合催化剂的氧催化性能最佳，ORR最大电流密度为290.1 mA/cm2 (-0.6 V vs Hg/HgO)，OER最大电流密度为390.5 mA/cm2 (1 V vs Hg/HgO)，明显高于单一催化剂。表明复合材料具有优异的氧催化性能。

Abstract:

Sr2Ni0.4Co1.6O6 double perovskite oxide was prepared by sol-gel method, and thin layer graphene was pre-pared by modified Hummers reduction method. They were synthesized as catalysts for bifunctional cata-lysts, and used to test its oxygen catalytic performance. The analysis results (XRD, EDS, SEM, IR etc) in-dicate that Sr2Ni0.4Co1.6O6 is homogeneously dispersed on the surface of graphene layers. Electrochemical performance tests show that the maximum current densities of single Sr2Ni0.4Co1.6O6 and thin layer gra-phene oxygen reduction reaction (ORR) are 183.0 mA/cm2 and 151.6 mA/cm2 (-0.6 V vs Hg/HgO), respec-tively, and the maximum current densities of the oxygen evolution reaction (OER) are 267.7 mA/cm2 and 117.4 mA/cm2(1 V vs Hg/HgO). When the amount of thin layer graphene add is 10 % of the mass of the composite catalyst, the composite catalyst has the best oxygen catalytic performance, the maximum cur-rent density of ORR is 290.1 mA/cm2(-0.6 V vs Hg/HgO), and the maximum current density of OER is 390.5 mA/cm2(1 V vs Hg/HgO). It shows that the composite has excellent oxygen catalytic performance than the single catalyst.