title: Designing a Highly Active Metal-Free Oxygen Reduction Catalyst in Membrane Electrode Assemblies for Alkaline Fuel Cells: Effects of Pore Size and Doping-Site Position.
abstract: To promote the oxygen reduction reaction of metal-free catalysts, the introduction of porous structure is considered as a desirable approach because the structure can enhance mass transport and host many catalytic active sites. However, most of the previous studies reported only half-cell characterization; therefore, studies on membrane electrode assembly (MEA) are still insufficient. Furthermore, the effect of doping-site position in the structure has not been investigated. Here, we report the synthesis of highly active metal-free catalysts in MEAs by controlling pore size and doping-site position. Both influence the accessibility of reactants to doping sites, which affects utilization of doping sites and mass-transport properties. Finally, an N,P-codoped ordered mesoporous carbon with a large pore size and precisely controlled doping-site position showed a remarkable on-set potential and produced 70% of the maximum power density obtained using Pt/C.
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Republic of Korea).
authors.forename: Seonggyu
authors.initials: S
authors.lastname: Lee
authors.affiliation: School of Environmental Science and Engineering, Gwangu Institute of Science and Technology, Gwangju 500-712 (Republic of Korea).
authors.forename: Myounghoon
authors.initials: M
authors.lastname: Choun
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Republic of Korea).
authors.forename: Youngjin
authors.initials: Y
authors.lastname: Ye
authors.affiliation: School of Environmental Science and Engineering, Gwangu Institute of Science and Technology, Gwangju 500-712 (Republic of Korea).
authors.forename: Jaeyoung
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Republic of Korea).
authors.forename: Yeongdong
authors.initials: Y
authors.lastname: Mun
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Republic of Korea).
authors.forename: Eunae
authors.initials: E
authors.lastname: Kang
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Republic of Korea).
authors.forename: Jongkook
authors.initials: J
authors.lastname: Hwang
authors.affiliation: Department of Chemical Engineering, Chungbuk National University, Cheongju 360-763 (Republic of Korea).
authors.forename: Young-Ho
authors.initials: YH
authors.lastname: Lee
authors.affiliation: Department of Chemical Engineering, Chungbuk National University, Cheongju 360-763 (Republic of Korea).
authors.forename: Chae-Ho
authors.initials: CH
authors.lastname: Shin
authors.affiliation: School of Environmental Science and Engineering, Gwangu Institute of Science and Technology, Gwangju 500-712 (Republic of Korea).
authors.forename: Seung-Hyeon
authors.initials: SH
authors.lastname: Moon
authors.affiliation: School of Integrative Engineering, Chung-Ang University, Seoul 156-756 (Republic of Korea).
authors.forename: Soo-Kil
authors.initials: SK
authors.lastname: Kim
authors.affiliation: Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Republic of Korea).
authors.forename: Eunsung
authors.initials: E
authors.lastname: Lee
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Republic of Korea). jinwoo03@postech.ac.kr.
authors.forename: Jinwoo
authors.initials: J
authors.lastname: Lee
keywords: electrocatalysis; fuel cells; mesoporous materials; metal-free catalysts; oxygen reduction reaction