Charge Transfer in the Fe/g-C₃N₄/MoS₂ Heterojunction: A Computational Study

We demonstrate, using density-functional calculations, that the interfacial charge transfer in the g-$\mathrm{C}_{3} \mathrm{~N}_{4} / \mathrm{MoS}_{2}$ heterojunction can be finely modulated by embedding transition metal atoms. Our findings reveal that introducing an Fe atom can either augment or diminish the charge flow between the graphitic $\mathbf{C}_{3} \mathbf{N}_{4}$ and MoS<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> layers, contingent upon its spatial positioning. The directionality of the induced electric field between the layers can be predicted through the computation of their respective work functions. These findings could help elucidate the experimentally observed enhancement in the photocatalytic performance of $\mathbf{g}$-$\mathrm{C}_{3} \mathrm{~N}_{4} / \mathrm{MoS}_{2}$ heterojunctions due to the incorporation of transition metal atoms. They also offer valuable guidance for the rational design of superior photocatalytic heterostructures.