title: Significant Enhancement of Water Splitting Activity of N-Carbon Electrocatalyst by Trace Level Co Doping.
abstract: Replacement of precious metal electrocatalysts with highly active and cost efficient alternatives for complete water splitting at low voltage has attracted a growing attention in recent years. Here, this study reports a carbon-based composite co-doped with nitrogen and trace amount of metallic cobalt (1 at%) as a bifunctional electrocatalyst for water splitting at low overpotential and high current density. An excellent electrochemical activity of the newly developed electrocatalyst originates from its graphitic nanostructure and highly active Co-Nx sites. In the case of carefully optimized sample of this electrocatalyst, 10 mA cm(-2) current density can be achieved for two half reactions in alkaline solutions-hydrogen evolution reaction and oxygen evolution reaction-at low overpotentials of 220 and 350 mV, respectively, which are smaller than those previously reported for nonprecious metal and metal-free counterparts. Based on the spectroscopic and electrochemical investigations, the newly identified Co-Nx sites in the carbon framework are responsible for high electrocatalytic activity of the Co,N-doped carbon. This study indicates that a trace level of the introduced Co into N-doped carbon can significantly enhance its electrocatalytic activity toward water splitting.
authors.affiliation: School of Chemical Engineering, the University of Adelaide, Adelaide, SA, 5005, Australia.
authors.forename: Bita
authors.initials: B
authors.lastname: Bayatsarmadi
authors.affiliation: School of Chemical Engineering, the University of Adelaide, Adelaide, SA, 5005, Australia.
authors.forename: Yao
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: School of Computer Science, Engineering & Mathematics, Flinders University, Adelaide, SA, 5001, Australia.
authors.forename: Youhong
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Department of Chemistry and Biochemistry, Kent State University, Kent, OH, 44240, USA.
authors.forename: Mietek
authors.initials: M
authors.lastname: Jaroniec
authors.affiliation: School of Chemical Engineering, the University of Adelaide, Adelaide, SA, 5005, Australia.
authors.forename: Shi-Zhang
authors.initials: SZ
authors.lastname: Qiao
keywords: carbon nanosheets; co-doping; hydrogen evolution reaction; oxygen evolution reaction; water splitting