title: A highly active and durable Co-N-C electrocatalyst synthesized using exfoliated graphitic carbon nitride nanosheets.
abstract: Exfoliated graphitic carbon nitride nanosheets (g-C3N4-NS) were applied for the first time for the preparation of an electrocatalyst for the oxygen reduction reaction (ORR). A less dense structure with increased surface area was observed for g-C3N4-NS compared to bulk g-C3N4 from detailed analyses including TEM, STEM, AFM with depth profiling, XRD, and UV-Vis spectroscopy. The pyrolysis of the prepared g-C3N4-NS with Co and carbon under an inert environment provided an enhanced accessibility to the N functionalities required for efficient interaction of Co and C with N for the formation of Co-N-C networks and produced a hollow and interconnected Co-N-C-NS structure responsible for high durability. The Co-N-C-NS electrocatalyst exhibited superior catalytic activity and durability and further displayed fast and selective four electron transfer kinetics for the ORR, as evidenced by various electrochemical experiments. The hollow, interconnected structure of Co-N-C-NS with increased pyridinic and graphitic N species has been proposed to play a key role in facilitating the desired ORR reaction.
authors.affiliation: Fuel Cell Research Center, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791, Republic of Korea. jinykim@kist.re.kr.
authors.forename: Jin Hee
authors.initials: JH
authors.lastname: Lee
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Park
authors.forename: Sung Jong
authors.initials: SJ
authors.lastname: Yoo
authors.forename: Jong Hyun
authors.initials: JH
authors.lastname: Jang
authors.forename: Hyoung-Juhn
authors.initials: HJ
authors.lastname: Kim
authors.forename: Suk Woo
authors.initials: SW
authors.lastname: Nam
authors.forename: Chang Won
authors.initials: CW
authors.lastname: Yoon
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Kim