STRAIN-ASSISTED TAILORING OF ELECTRONIC AND PHOTOCATALYTIC RESPONSE OF AlN-MoX ₂ (X = S, Se, Te) HETEROSTRUCTURES: A DENSITY FUNCTIONAL THEORY-BASED APPROACH

Motivated by the pressing need to address environmental issues and the global energy crisis, significant potential lies in utilizing solar energy for water splitting to generate hydrogen fuel. To realize this technology, the development of efficient and cost-competitive photocatalysts is paramount. Recently, van der Waals (vdW) heterostructures have garnered considerable attention due to their unique properties, making them particularly promising candidates in this field. This study employs density functional theory (DFT) to comprehensively investigate the electronic and photocatalytic properties of AlN-MoX 2 vdW heterostructures. Here, X represents sulfur, selenium, and tellurium. Through the analysis of various stacking configurations, the most energetically favorable structure is identified based on its relaxation energy. Binding energies further provide corroboration for the stability of the chosen configuration. Analysis of the calculated band structures reveals that AlN-MoS 2 exhibits direct bandgap characteristics, while AlN-MoSe 2 and AlN-MoTe 2 display indirect band gaps. Additionally, AlN-MoS 2 and AlN-MoSe 2 demonstrate a Type-II band alignment, whereas AlN-MoTe 2 exhibits Type-I band alignment. By evaluating the valence and conduction band edges, we assessed the photocatalytic performance of these heterostructures (at pH [Formula: see text] 0). Our analysis confirms the efficacy of unstrained AlN-MoSe 2 heterostructures as efficient photocatalysts under these conditions, based on their observed photocatalytic behavior.