title: Nitrogen-Doped Carbon Nanoparticle-Carbon Nanofiber Composite as an Efficient Metal-Free Cathode Catalyst for Oxygen Reduction Reaction.
abstract: Metal-free nitrogen-doped carbon materials are currently considered at the forefront of potential alternative cathode catalysts for the oxygen reduction reaction (ORR) in fuel cell technology. Despite numerous efforts in this area over the past decade, rational design and development of a new catalyst system based on nitrogen-doped carbon materials via an innovative approach still present intriguing challenges in ORR catalysis research. Herein, a new kind of nitrogen-doped carbon nanoparticle-carbon nanofiber (NCNP-CNF) composite with highly efficient and stable ORR catalytic activity has been developed via a new approach assisted by a solution plasma process. The integration of NCNPs and CNFs by the solution plasma process can lead to a unique morphological feature and modify physicochemical properties. The NCNP-CNF composite exhibits a significantly enhanced ORR activity through a dominant four-electron pathway in an alkaline solution. The enhancement in ORR activity of NCNP-CNF composite can be attributed to the synergistic effects of good electron transport from highly graphitized CNFs as well as abundance of exposed catalytic sites and meso/macroporosity from NCNPs. More importantly, NCNP-CNF composite reveals excellent long-term durability and high tolerance to methanol crossover compared with those of a commercial 20 wt % supported on Vulcan XC-72. We expect that NCNP-CNF composite prepared by this synthetic approach can be a promising metal-free cathode catalyst candidate for ORR in fuel cells and metal-air batteries.
authors.affiliation: Department of Materials Science and Engineering, Faculty of Engineering, Shibaura Institute of Technology , 3-7-5 Toyosu, Koto-ku, Tokyo 135-8548, Japan.
authors.forename: Gasidit
authors.initials: G
authors.lastname: Panomsuwan
authors.affiliation: Department of Materials, Physics and Energy Engineering, Graduate School of Engineering, Nagoya University , Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.|Social Innovation Design Center (SIDC), Institute of Innovation for Future Society, Nagoya University , Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.|Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST) , 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Nagahiro
authors.initials: N
authors.lastname: Saito
authors.affiliation: Department of Materials Science and Engineering, Faculty of Engineering, Shibaura Institute of Technology , 3-7-5 Toyosu, Koto-ku, Tokyo 135-8548, Japan.|Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST) , 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Ishizaki
keywords: fuel cells; nitrogen-doped carbon materials; oxygen reduction reaction; solution plasma process