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Quantum dot-sensitized O-linked heptazine polymer photocatalyst for the metal-free visible light hydrogen generation.

ABSTRACT: Metal-free organic polymer photocatalysts have attracted dramatic attention in the field of visible light-induced hydrogen evolution reaction (HER). Herein, we showed a polymeric O-linked heptazine polymer (OLHP) decorated with S, N co-doped graphene quantum dots (S,N-GQDs) as a photosensitizer to generate hydrogen upon quantum dot sensitization. Both of these heptazine-based systems show effective photosensitization with strong π-π interactions and enhanced photocatalytic H₂ generation (24 times) as metal-free systems. Electrochemical impedance and optical measurements show effective charge transfer kinetics with decreased charge recombination, which is responsible for the enhanced photocatalytic activity. As a result, a significant high apparent quantum yield (AQY) with highest value of 10.2% was obtained for our photocatalyst OLHP/S,N-GQD10.

SUBMITTER: Samanta S

PROVIDER: S-EPMC9056167 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Quantum dot-sensitized O-linked heptazine polymer photocatalyst for the metal-free visible light hydrogen generation.

Samanta Soumadri S Kumar Sunil S Battula V R VR Jaryal Arpna A Sardana Neha N Kailasam Kamalakannan K

RSC advances 20200811 50

Metal-free organic polymer photocatalysts have attracted dramatic attention in the field of visible light-induced hydrogen evolution reaction (HER). Herein, we showed a polymeric O-linked heptazine polymer (OLHP) decorated with S, N co-doped graphene quantum dots (S,N-GQDs) as a photosensitizer to generate hydrogen upon quantum dot sensitization. Both of these heptazine-based systems show effective photosensitization with strong π-π interactions and enhanced photocatalytic H<sub>2</sub> generati ...[more]

PMID: 35518248

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