Ordered Mesoporous C3N5 with a Combined Triazole and Triazine Framework and Its Graphene Hybrids for the Oxygen Reduction Reaction (ORR)

• Published in: Angewandte Chemie International Edition Vol. 57; no. 52; pp. 17135 - 17140
• Main Authors: Kim, In Young, Kim, Sungho, Jin, Xiaoyan, Premkumar, Selvarajan, Chandra, Goutam, Lee, Nam‐Suk, Mane, Gurudas P., Hwang, Seong‐Ju, Umapathy, Siva, Vinu, Ajayan
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 21-12-2018
• Edition: International ed. in English
• Subjects: Biotechnology; Bulk density; Carbon nitride; Catalysis; Chemical reduction; Chemical synthesis; electrocatalysts; Graphene; Hybrids; N-rich carbon nitrides; Organic chemistry; Oxygen; oxygen reduction reaction; Oxygen reduction reactions; porous materials; Silica; Silicon dioxide; Stoichiometry; Tetrazoles; Triazine; triazoles
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201811061

Mesoporous carbon nitrides (MCN) with C3N4 stoichiometry could find applications in fields ranging from catalysis, sensing, and adsorption–separation to biotechnology. The extension of the synthesis of MCN with different nitrogen contents and chemical structures promises access to a wider range of applications. Herein we prepare mesoporous C3N5 with a combined triazole and triazine framework via a simple self‐assembly of 5‐amino‐1H‐tetrazole (5‐ATTZ). We are able to hybridize these nanostructures with graphene by using graphene–mesoporous‐silica hybrids as a template to tune the electronic properties. DFT calculations and spectroscopic analyses clearly demonstrate that the C3N5 consists of 1 triazole and 2 triazine moieties. The triazole‐based mesoporous C3N5 and its graphene hybrids are found to be highly active for oxygen reduction reaction (ORR) with a higher diffusion‐limiting current density and a decreased overpotential than those of bulk g‐C3N4.
Triazole you might: In the oxygen reduction reaction (ORR) triazole‐based C3N5 (MCN‐11) and its graphene hybrids show significantly improved diffusion‐limiting current density compared to g‐C3N4. The enhanced activity is attributed to features of MCN‐11 such as strong adsorption between O2 and active carbons in the triazole moiety.