Density functional theory (DFT) is employed to study the electronic structures and properties of the g-C₃N₄/Bi₂MoO₆ (BMO) (010) heterojunction, and the energy band, density of states (DOS), and charge transfer properties are analyzed to reveal the microscopic mechanism. Band structure calculations reveal that the g-C₃N₄/Bi₂MoO₆(010) heterojunction possesses a direct band gap, which is substantially narrower than those of its individual g-C₃N₄ and BMO constituents, thereby facilitating electron transition and significantly enhancing its visible-light absorption. Analysis of the DOS reveals that the valence band maximum (VBM) of the heterojunction primarily originates from the N 2p orbitals of g-C₃N₄, while the conduction band minimum (CBM) is mainly composed of the Bi 6p and Mo 4d orbitals of Bi₂MoO₆. The different orbitals at VBM and CBM enable effective separation of electron-hole pairs, which significantly reduces the charge carrier recombination. Furthermore, analysis of the charge density difference and work function reveals a clear interfacial charge redistribution at the g-C₃N₄/Bi₂MoO₆(010) interface, which effectively promotes the separation of photogenerated carriers and inhibits their recombination. These findings provide a crucial theoretical foundation for guiding the design of high-performance photocatalytic heterostructures and highlight their significant potential for practical applications.

Huihui Shi, Shiheng Xin, Fuchun Zhang. First-Principles Study of the Photocatalytic Echanism Based on the g-C₃N₄/Bi₂MoO₆ (010) Heterojunction. Academic Journal of Materials & Chemistry (2026), Vol. 7, Issue 1: 26-33. https://doi.org/10.25236/AJMC.2026.070105.

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