铂/石墨烯氧还原电催化剂的共还原法制备及表征

使用硼氢化钠共还原法制备40% (w)铂/石墨烯电催化剂用于氧还原反应. 通过循环伏安测试发现, 这种方法制备所得铂/石墨烯催化剂对氧还原反应活性较铂/碳催化剂差, 但稳定性有所提高. 在稳定性测试中,铂/石墨烯电催化性能衰减为50%, 较铂/碳(79%)好. X射线衍射(XRD)和透射电子显微镜(TEM)表征发现在铂/石墨烯催化剂中两者存在明显交互作用, 这可能是阻止石墨烯再堆垛和防止铂颗粒团聚的主要原因. 通过对单电池性能测试也发现铂/石墨烯催化剂更有利于电池长期稳定.

Synthesis and Characteristics of Pt/graphene by Co-Reduction Method for Oxygen Reduction Reactions

40% (w) Pt/graphene composites were prepared by sodium borohydride chemical coreduction, and were subsequently used as an electrocatalyst for oxygen reduction reactions. The electrocatalytic activity and stability was evaluated by cyclic voltammetry. The results indicated that the initial activity of Pt/graphene was lower than that of Pt/C due to the oxygen diffusion inhibition; however, the Pt/graphene showed superior durability characteristics. Degradation tests showed a 50% degradation of Pt/ graphene, which was substantially less than that of Pt/C (79%). X-ray diffraction and transmission electron microscope results showed that the composite formed strong interactions between the platinum nanoparticles and the graphene supports. The graphene supports may also prevent the graphene sheets from folding or re-stacking, which would hinder platinum nanoparticles'' aggregation. The performance of a single cell was also tested, confirming an improvement in durability.