Nitrogen-doped graphene with a three-dimensional architecture assisted by carbon nitride tetrapods as an efficient metal-free electrocatalyst for hydrogen evolution

TitleNitrogen-doped graphene with a three-dimensional architecture assisted by carbon nitride tetrapods as an efficient metal-free electrocatalyst for hydrogen evolution
Publication TypeJournal Article
Year of Publication2017
AuthorsGangadharan, PK, Unni, SKM, Kumar, N, Ghosh, P, Kurungot, S
JournalChemelectrochem
Volume4
Issue10
Pagination2643-2652
Date PublishedOCT
Type of ArticleArticle
ISSN2196-0216
Keywordscarbon nitride, Density functional theory, electrocatalyst, hydrogen evolution reaction, nitrogen doped graphene
AbstractCurrent polymer membrane-based electrolyzers use Pt as a cathode catalyst for efficient reduction of water. The high cost of Pt-based catalysts forces researchers to develop alternative electrocatalysts. Here, a simple strategy has been proposed to synthesize a metal-free electrocatalyst for the hydrogen evolution reaction (HER) by high-temperature annealing of graphene oxide-coated melamine foam. The prepared catalyst possesses both structural and functional advantages with its three-dimensional (3D) interconnected arms of carbon nitride (CNx) backbone wrapped with nitrogen-doped graphene (N-RGO) sheets (CNx@N-RGO). CNx@N-RGO faces only a 193 mV overpotential to achieve a current density of 10mAcm(-2), which is far superior to the previously reported Pt-free systems. Along with the high exchange current density 34.7 x 10(-6)A cm(-2) and low Tafel slope of 54 mV dec(-1), CNx@N-RGO follows a Volmer-Heyrovsky mechanism for the HER. DFT calculations show that the synergy between CNx and N-RGO facilitates good electrical coupling between the two moieties and provides optimal binding to H+ ions on the catalyst that, in turn, results in efficient reduction of hydrogen ions.
DOI10.1002/celc.201700479
Type of Journal (Indian or Foreign)Foreign
Impact Factor (IF)4.136
Divison category: 
Physical and Materials Chemistry