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Item details URL: http://open-repository.kisti.re.kr/cube/handle/open_repository/473425.do

Title: 3D graphene preparation via covalent amide functionalization forefficient metal-free electrocatalysis in oxygen reduction

Description: This work was supported in part by the National Research Foundation ofKorea (15H1C1A1035825 and 15R1A4A1041746) and in part by Korea ElectricPower Cooperation (KEPCO).

abstract: 3D and porous reduced graphene oxide (rGO) catalysts have been prepared with sp(3)-hybridized 1,4-diaminobutane (sp(3)-DABu, rGO-sp(3)-rGO) and sp(2)-hybridized 1,4-diaminobenzene (sp(2)-DABe, rGO-sp(2)-rGO) through a covalent amidation and have employed as a metal-free electrocatalyst for oxygen reduction reaction (ORR) in alkaline media. Both compounds have used as a junction between functionalized rGO layers to improve electrical conductivity and impart electrocatalytic activity to the ORR resulting from the interlayer charge transfer. The successful amidation and the subsequent reduction in the process of catalyst preparation have confirmed by X-ray photoelectron spectroscopy. A hierarchical porous structure is also confirmed by surface morphological analysis. Specific surface area and thermal stability have increased after successful the amidation by sp(3)-DABu. The investigated ORR mechanism reveals that both functionalized rGO is better ORR active than nonfunctionalized rGO due to pyridinic-like N content and rGO-sp(3)-rGO is better ORR active than rGO-sp(2)-rGO due to higher pyridinic-like N content and pi-electron interaction-free interlayer charge transfer. Thus, the rGO-sp(3)-rGO has proven as an efficient metal-free electrocatalyst with better electrocatalytic activity, stability, and tolerance to the crossover effect than the commercially available Pt/C for ORR.

provenance: Made available in Cube on 2018-09-28T10:19:11Z (GMT). No. of bitstreams: 0

uri: http://open-repository.kisti.re.kr/cube/handle/open_repository/473425.do

3D graphene preparation via covalent amide functionalization forefficient metal-free electrocatalysis in oxygen reduction