Electrospun Nb-doped TiO2 nanofiber support for Pt nanoparticles with high electrocatalytic activity and durability

MinJoong Kim; ChoRong Kwon; KwangSup Eom; JiHyun Kim; EunAe Cho

doi:10.1038/srep44411

Electrospun Nb-doped TiO₂ nanofiber support for Pt nanoparticles with high electrocatalytic activity and durability

Sci Rep. 2017 Mar 14:7:44411. doi: 10.1038/srep44411.

Authors

MinJoong Kim¹, ChoRong Kwon^{2

3}, KwangSup Eom⁴, JiHyun Kim², EunAe Cho¹

Affiliations

¹ Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
² Department of Energy Environment Policy and Technology, Green School, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea.
³ Fuel Cell Research Center, Korea Institute of Science and Technology (KIST), 5 Hwarang-ro 14-gil, Seongbuk-gu, Seoul, 02792, Republic of Korea.
⁴ School of Materials and Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea.

Abstract

This study explores a facile method to prepare an efficient and durable support for Pt catalyst of polymer electrolyte membrane fuel cell (PEMFC). As a candidate, Nb-doped TiO₂ (Nb-TiO₂) nanofibers are simply fabricated using an electrospinning technique, followed by a heat treatment. Doping Nb into the TiO₂ nanofibers leads to a drastic increase in electrical conductivity with doping level of up to 25 at. % (Nb_0.25Ti_0.75O₂). Pt nanoparticles are synthesized on the prepared 25 at. % Nb-doped TiO₂-nanofibers (Pt/Nb-TiO₂) as well as on a commercial powdered carbon black (Pt/C). The Pt/Nb-TiO₂ nanofiber catalyst exhibits similar oxygen reaction reduction (ORR) activity to that of the Pt/C catalyst. However, during an accelerated stress test (AST), the Pt/Nb-TiO₂ nanofiber catalyst retained more than 60% of the initial ORR activity while the Pt/C catalyst lost 65% of the initial activity. The excellent durability of the Pt/Nb-TiO₂ nanofiber catalyst can be attributed to high corrosion resistance of TiO₂ and strong interaction between Pt and TiO₂.

Publication types

Research Support, Non-U.S. Gov't