Premium
Mechanistic Understanding of Size‐Dependent Oxygen Reduction Activity and Selectivity over Pt/CNT Nanocatalysts
Author(s) -
Gan Jie,
Luo Wei,
Chen Wenyao,
Guo Jianing,
Xiang Zhonghua,
Chen Bingxu,
Yang Fan,
Cao Yunjun,
Song Fei,
Duan Xuezhi,
Zhou Xinggui
Publication year - 2019
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/ejic.201801521
Subject(s) - nanomaterial based catalyst , chemistry , catalysis , density functional theory , high resolution transmission electron microscopy , selectivity , x ray photoelectron spectroscopy , active site , electrochemistry , octahedron , carbon nanotube , nanoparticle , oxygen , nanotechnology , oxygen reduction reaction , chemical engineering , computational chemistry , crystallography , crystal structure , materials science , organic chemistry , electrode , transmission electron microscopy , engineering
Identifying the underlying nature of the structure sensitivity of oxygen reduction reaction (ORR) over carbon supported Pt catalysts is an important but challenging issue in electrochemical system. In this work, we combine experiments, density functional theory calculations with model calculations to clarify the size‐dependent ORR activity and selectivity over differently sized Pt/CNT catalysts. HAADF‐STEM, HRTEM and XPS measurements show that the Pt nanoparticles supported on CNT possess a well‐defined truncated octahedron shape in most cases and similar electronic properties. The observed size‐insensitive TOF active site based on the number of Pt(111) atoms suggests the Pt(111) surface as the dominant active site. Moreover, the Pt(111) surface is also suggested as the dominant active sites for the formation of H 2 O 2 , and the catalyst with the higher Pt binding energy facilitates the oxygen reduction to H 2 O. The insights revealed here could shed new light on the design and optimization of Pt‐based ORR catalysts.