Anchoring ultrafine Pt electrocatalysts on TiO2-C via photochemical strategy to enhance the stability and efficiency for oxygen reduction reaction

• Published in: Applied catalysis. B, Environmental Vol. 237; pp. 228 - 236
• Main Authors: Wang, Jingyu, Xu, Min, Zhao, Jianquan, Fang, Huaifang, Huang, Qingzhu, Xiao, Weiping, Li, Tao, Wang, Deli
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.12.2018
• Subjects: Oxygen reduction reaction; Photochemical deposition; Pt electrocatalysts; Strong metal-support interaction; TiO2-C support; Pt electrocatalysts; Photochemical deposition; Oxygen reduction reaction; Strong metal-support interaction; TiO2-C support
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2018.05.085

[Display omitted] •Ultrafine Pt was anchored around TiO2 surface by green photochemical strategy.•Direct reduction by TiO2 strengthened the interaction between Pt and support.•The Pt/TiO2-C exhibited superior ORR catalytic activity to commercial Pt/C.•The stability of Pt is greatly enhanced by the electronic interaction with TiO2-C. The activity and stability of Pt electrocatalysts are crucial issues for energy conversion systems involving oxygen reduction reaction (ORR). In this work, the ultrafine Pt nanoparticles were in situ reduced by the photogenerated electrons on TiO2 surface so that most of them selectively anchored around the TiO2 nanocrystals. The presence of well-dispersed TiO2 on carbon surface strengthened the metal-support interaction, giving rise to the improved ORR catalytic activity with ∼49 mV positive shift of half-wave potential as compared to commercial 20 wt% Pt/C. More importantly, the Pt/TiO2-C catalysts exhibited a more durable performance after 10,000 cycles in terms of the decrease in electrochemical surface area (0.8%) and mass activity (0.9%), much lower than those of Pt/C (10.2% and 33.3%). The high-temperature durability test also revealed a much higher retention of ORR activity. The results demonstrated that anchoring Pt on well-dispersed TiO2-decorated carbon would be an effective strategy to enhance the ORR performance by strong metal-support interaction, which facilitated the electron transfer during catalytic reactions as well as prevented Pt aggregation during durability test.