An advanced electrocatalyst of Pt decorated SnO2/C nanofibers for oxygen reduction reaction

作者:Zhang, Kai; Feng, Chuanqi; He, Bingyu; Dong, Haifeng*; Dai, Wenhao; Lu, Huiting; Zhang, Xueji*
来源:Journal of Electroanalytical Chemistry, 2016, 781: 198-203.
DOI:10.1016/j.jelechem.2016.11.002

摘要

In this report, an efficient oxygen reduction reaction (ORR) electrocatalyst of platinum (Pt) decorated SnO2/C (Pt/SnO2/C) nanofiber was fabricated by using a Pt galvanic displacement of a copper (Cu) layer electrodeposited on electrospinning SnO2/C nanofiber. Microscopic and spectroscopic characterizations revealed that the facile elecstrospinning and galvanic displacement route generated numerous dispersed Pt nanoparticles on the SnO2/C nanofiber; and Pt nanoparticles (d similar to 2-3 nm) with high composition of Pt (111) facet were preferably deposited at the SnO2/C junctions to form triple junction nanostructures. The resulting Pt/SnO2/C nanocomposite presented an onset potential of 0.02 V vs RHE, specific activity of 1.12 mA cm(-2) and mass activity of 615 mA/mg(Pt) at -0.05 V vs RHE. It is competitive to commercial Pt/C (10 wt% Pt) catalyst toward ORR. Notably, in comparison with commercial Pt/C, the composition displayed superior electrochemical durability and enhanced methanol tolerance. It was demonstrated that the presence of Pt/SnO2/C triple junction nanostructures coupled with high composition of Pt (111) facets synergistically contributed the enhanced ORR activity, while the good conductivity of the C facilitates the electron transfer during the ORR process. The metal-metal oxide-carbonaceous heterogeneous structure represents a promising platform for designing ORR catalysts with high performance.