Zheng Yuanyuan, Qiao Junhua, Yuan Junhua, Shen Jianfeng, Wang Ai-Jun, Gong Peijun
Key laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Life Sciences and Chemistry, College of Geography and Environmental Science, Zhejiang Normal University, Jinhua, Zhejiang, 321004 People's Republic of China.
Nanotechnology. 2018 Mar 9;29(10):10LT01. doi: 10.1088/1361-6528/aaa809.
How to use Pt economically and efficiently in the oxygen reduction reaction (ORR) is of theoretical and practical significance for the industrialization of the proton-exchange membrane fuel cells. In order to minimize Pt consumption and optimize the ORR performance, the ORR catalysts are recommended to be designed as a porous nanostructure. Herein, we report a one-pot solvothermal strategy to prepare PtPd dendritic nanocube cages via a galvanic replacement mechanism triggered by an I ion. These PtPd alloy crystals are nanoporous, and uniformly dispersed on reduced graphene oxides (RGOs). The size of the PtPd dendritic nanocube cages can be easily tuned from 20-80 nm by controlling their composition. Their composition is optimized to be 1:5 Pt/Pd atomic ratio for these RGO-supported PtPd dendritic nanocages. This catalyst shows superior ORR performance with a specific activity of 2.01 mA cm and a mass activity of 4.45 A mg Pt, far above those for Pt/C catalysts (0.288 mA cm for specific activity, and 0.21 A mg Pt for mass activity). In addition to ORR activity, it also exhibits robust durability with almost negligible decay in ORR mass activity after 10 000 voltammetric cycling.
如何在氧还原反应（ORR）中经济高效地使用铂对于质子交换膜燃料电池的工业化具有理论和实际意义。为了最小化铂的消耗并优化ORR性能，建议将ORR催化剂设计成多孔纳米结构。在此，我们报道了一种一锅法溶剂热策略，通过碘离子引发的电化置换机制制备PtPd树枝状纳米立方笼。这些PtPd合金晶体是纳米多孔的，并均匀地分散在还原氧化石墨烯（RGO）上。通过控制其组成，PtPd树枝状纳米立方笼的尺寸可以轻松地在20至80纳米之间调节。对于这些RGO负载的PtPd树枝状纳米笼，其组成被优化为1:5的Pt/Pd原子比。这种催化剂表现出优异的ORR性能，比活性为2.01 mA cm，质量活性为4.45 A mg Pt，远高于Pt/C催化剂（比活性为0.288 mA cm，质量活性为0.21 A mg Pt）。除了ORR活性外，它还表现出强大的耐久性，在10000次伏安循环后，ORR质量活性几乎没有衰减。
