Highly efficient and durable TiN nanofiber electrocatalyst supports.
To date, carbon-based materials including various carbon nanostructured materials have been extensively used as an electrocatalyst support for proton exchange membrane fuel cell (PEMFC) applications due to their practical nature. However, carbon dissolution or corrosion caused by high electrode potential in the presence of O2 and/or water has been identified as one of the main failure modes for the device operation. Here, we report the first TiN nanofiber (TNF)-based nonwoven structured materials to be constructed via electrospinning and subsequent two-step thermal treatment processes as a support for the PEMFC catalyst. Pt catalyst nanoparticles (NPs) deposited on the TNFs (Pt/TNFs) were electrochemically characterized with respect to oxygen reduction reaction (ORR) activity and durability in an acidic medium. From the electrochemical tests, the TNF-supported Pt catalyst was better and more stable in terms of its catalytic performance compared to a commercially available carbon-supported Pt catalyst. For example, the initial oxygen reduction performance was comparable for both cases, while the Pt/TNF showed much higher durability from an accelerated degradation test (ADT) configuration. It is understood that the improved catalytic roles of TNFs on the supported Pt NPs for ORR are due to the high electrical conductivity arising from the extended connectivity, high inertness to the electrochemical environment and strong catalyst-support interactions.
Fuel Cell Research Center, Korea Institute of Science and Technology, Seongbuk-Gu, Seoul 136-791, Republic of Korea. jinykim@kist.re.kr.
Hyun
H
Kim
Min Kyung
MK
Cho
Jeong An
JA
Kwon
Yeon Hun
YH
Jeong
Kyung Jin
KJ
Lee
Na Young
NY
Kim
Min Jung
MJ
Kim
Sung Jong
SJ
Yoo
Jong Hyun
JH
Jang
Hyoung-Juhn
HJ
Kim
Suk Woo
SW
Nam
Dong-Hee
DH
Lim
EunAe
E
Cho
Kwan-Young
KY
Lee
Jin Young
JY
Kim