Chen Xu, He Daping, Wu Hui, Zhao Xiaofeng, Zhang Jian, Cheng Kun, Wu Peng, Mu Shichun
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China.
Sci Rep. 2015 Nov 5;5:16246. doi: 10.1038/srep16246.
For the first time a novel oxygen reduction catalyst with a 3D platinized graphene/nano-ceramic sandwiched architecture is successfully prepared by an unusual method. Herein the specific gravity of graphene nanosheets (GNS) is tailored by platinizing graphene in advance to shorten the difference in the specific gravity between carbon and SiC materials, and then nano-SiC is well intercalated into GNS interlayers. This nano-architecture with highly dispersed Pt nanoparticles exhibits a very high oxygen reduction reaction (ORR) activity and polymer electrolyte membrane (PEM) fuel cell performance. The mass activity of half cells is 1.6 times of that of the GNS supported Pt, and 2.4 times that of the commercial Pt/C catalyst, respectively. Moreover, after an accelerated stress test our catalyst shows a predominantly electrochemical stability compared with benchmarks. Further fuel cell tests show a maximum power density as high as 747 mW/cm(2) at low Pt loading, which is more than 2 times higher than that of fuel cells with the pristine graphene electrode.
首次通过一种不同寻常的方法成功制备了具有三维镀铂石墨烯/纳米陶瓷夹层结构的新型氧还原催化剂。在此，通过预先对石墨烯进行镀铂来调整石墨烯纳米片（GNS）的比重，以缩短碳材料和SiC材料之间的比重差异，然后将纳米SiC很好地插入到GNS层间。这种具有高度分散的Pt纳米颗粒的纳米结构表现出非常高的氧还原反应（ORR）活性和聚合物电解质膜（PEM）燃料电池性能。半电池的质量活性分别是GNS负载Pt的1.6倍和商业Pt/C催化剂的2.4倍。此外，经过加速应力测试后，与基准相比，我们的催化剂显示出主要的电化学稳定性。进一步的燃料电池测试表明，在低Pt负载量下，最大功率密度高达747 mW/cm²，这比使用原始石墨烯电极的燃料电池高出两倍多。
