期刊
SN APPLIED SCIENCES
卷 1, 期 11, 页码 -出版社
SPRINGER INTERNATIONAL PUBLISHING AG
DOI: 10.1007/s42452-019-1478-0
关键词
Density functional theory; Platinum nanoparticles; SnO2; Support effect; Polymer electrolyte fuel cells
资金
- KYOCERA Corporation
- ACCEL, Japan Science and Technology Agency [JPMJAC1501]
- Advanced Computational Scientific Program of Research Institute for Information Technology, Kyushu University
While Pt-nanoparticles supported on SnO2 exhibit improved durability, a substantial detriment is observed on the Ptnanoparticles' activity toward the oxygen reduction reaction. A density functional theory method is used to calculate isolated, SnO2- and graphene-supported Pt-nanoparticles. Work function difference between the Pt-nanoparticles and SnO2 leads to electron donation from the nanoparticles to the support, making the outer-shell atoms of the supported nanoparticles more positively charged compared to unsupported nanoparticles. From an electrostatic point of view, nucleophilic species tend to interact more stably with less negatively charged Pt atoms blocking the active sites for the reaction to occur, which can explain the low activity of Pt-nanoparticles supported on SnO2. Introducing oxygen vacancies and Nb dopants on SnO2 decreases the support work function, which not only reduces the charge transferred from the Pt-nanoparticles to the support but also reverses the direction of the electrons flow making the surface Pt atoms more negatively charged. A similar effect is observed when using graphene, which has a lower work function than Pt. Thus, the blocking of the active sites by nucleophilic species decreases, hence increasing the activity. These results provide a clue to improve the activity by modifying the support work function and by selecting a support material with an appropriate work function to control the charge of the nanoparticle's surface atoms. [GRAPHICS] .
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据