Kou Zongkui, Cheng Kun, Wu Hui, Sun Ronghui, Guo Beibei, Mu Shichun
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology , Wuhan 430070, China.
ACS Appl Mater Interfaces. 2016 Feb 17;8(6):3940-7. doi: 10.1021/acsami.5b11086. Epub 2016 Feb 4.
The radical degradation of Pt-based catalysts toward oxygen reduction reaction (ORR), predominantly caused by the oxidation of carbon supports, heavily blocks the commercialization of polymer electrolyte membrane fuel cells (PEMFCs). As reported, the electrochemical oxidation of carbon could be accelerated by Pt catalysts; however, hitherto no direct evidence is present for the promotion of Pt catalysts. Herein, a unique ultrathin carbon layer (approximately 2.9 nm in thickness) covered Pt catalyst (Pt/C-GC) is designed and synthesized by a chemical vapor deposition (CVD) method. This magnifies the catalysis effect of Pt to carbon oxidation due to the greatly increased contact sites between the metal-support, making it easy to investigate the carbon oxidation process by observing the thinning of the carbon layer on Pt nanoparticles from TEM observations. Undoubtedly, this finding can better guide the structural design of the durable metal catalysts for PEMFCs and other applications.
铂基催化剂对氧还原反应(ORR)的剧烈降解,主要是由碳载体的氧化引起的,这严重阻碍了聚合物电解质膜燃料电池(PEMFC)的商业化。据报道,碳的电化学氧化可被铂催化剂加速;然而,迄今为止,尚无促进铂催化剂作用的直接证据。在此,通过化学气相沉积(CVD)方法设计并合成了一种独特的覆盖有超薄碳层(厚度约为2.9 nm)的铂催化剂(Pt/C-GC)。由于金属-载体之间的接触位点大幅增加,这放大了铂对碳氧化的催化作用,使得通过透射电子显微镜(TEM)观察铂纳米颗粒上碳层的变薄情况来研究碳氧化过程变得容易。毫无疑问,这一发现能够更好地指导用于PEMFC及其他应用的耐用金属催化剂的结构设计。