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Ultrafast hydrogen production in boron/oxygen-codoped graphitic carbon nitride revealed by nonadiabatic dynamics simulations.

Authors :
Yang, Huijuan
Wu, Rongliang
Li, Wei
Wen, Jin
Source :
Physical Chemistry Chemical Physics (PCCP); 5/21/2024, Vol. 26 Issue 19, p14205-14215, 11p
Publication Year :
2024

Abstract

Graphitic carbon nitride (g-C<subscript>3</subscript>N<subscript>4</subscript> or GCN) shows promise in photocatalytic water splitting, despite facing the challenge of rapid electron–hole recombination. In this study, we investigated the influence of boron/oxygen codoping on the photocatalytic performance of GCN systems for hydrogen generation. First-principles calculations and nonadiabatic molecular dynamics (NAMD) simulations were employed to reveal that the recombination time of photogenerated carriers could be increased by 16% to 64% in the codoped systems compared to the pristine GCN. The time-dependent density functional theory (TDDFT) scheme was utilized to select energy windows and initiate dynamics in cluster models of B/O co-doped heptazine with water molecules. Notably, we observed efficient direct photodissociation of hydrogen atoms from water molecules within 60 fs and proton hops within the hydrogen-bonded network within 80 fs in the co-doped system, diverging from the previously proposed mechanism for pristine heptazine in NAMD simulations. This discovery underscores the significant role of faster proton-coupled electron transfer (PCET) reactions and rapid radiationless relaxation in achieving high photocatalytic efficiency in water splitting. Our work enhances the understanding of the internal mechanism of highly efficient photocatalysts for water splitting and provides a new design strategy for doped GCN. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
14639076
Volume :
26
Issue :
19
Database :
Complementary Index
Journal :
Physical Chemistry Chemical Physics (PCCP)
Publication Type :
Academic Journal
Accession number :
177400869
Full Text :
https://doi.org/10.1039/d4cp01085j