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Enhancing Photocatalytic Hydrogen Production of g-C₃N₄ by Selective Deposition of Pt Cocatalyst.

ABSTRACT: Graphitic carbon nitride (g-C₃N₄) has been widely studied as a photocatalyst for the splitting of water to produce hydrogen. In order to solve the problems of limited number of active sites and serious recombination rate of charge-carriers, noble metals are needed as cocatalysts. Here, we selectively anchored Pt nanoparticles (NPs) to specific nitrogen species on the surface of g-C₃N₄ via heat treatment in argon-hydrogen gas mixture, thus achieving g-C₃N₄ photocatalyst anchored by highly dispersed homogeneous Pt NPs with the co-existed metallic Pt⁰ and Pt²⁺ species. The synergistic effect of highly dispersed metallic Pt⁰ and Pt²⁺ species makes the catalyst exhibit excellent photocatalytic performance. Under the full-spectrum solar light irradiation, the photocatalytic hydrogen production rate of the photocatalyst is up to 18.67 mmol·g^-1·h^-1, which is 5.1 times of the catalyst prepared by non-selective deposition of Pt NPs.

SUBMITTER: Li Y

PROVIDER: S-EPMC8709060 | biostudies-literature |

REPOSITORIES: biostudies-literature

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