Computational Analysis of the Electronic Band Structure in Monolayer Nb₃TeCl₇

2D breathing Kagomé materials have recently garnered significant attention for exploring topology and magnetism in quantum materials. Among these, Nb₃TeCl₇ shows considerable promise in a wide range of applications, including photocatalytic water splitting, a critical process for sustainable hydrogen production. In this study, we employ Density Functional Theory (DFT) simulations using the Vienna Ab initio Simulation Package (VASP) to investigate the electronic band structure of monolayer Nb₃TeCl₇. Our analysis identifies specific orbital contributions to each electronic band. We use variations in the Hubbard U parameter, which is an effective on-site Coulomb repulsion energy introduced in DFT+U to correct the self-interaction error in localized d/f orbital, while also mimicking strain and pressure induced effects. We show tunability of the bandgap from 0.78eV to 1.41eV by sweeping across six Hubbard U values of 0-5eV. This allows for the material to be calibrated to ideal conditions for water spliting, which requires a specific bandgap energy of 1.23eV. In addition, a higher bandgap reduces the impact of two-photon absorption in semicondotors, further strengthening Nb₃TeCl₇ as a candidate for 2D semiconductor applications, and nonlinear optics. This work underscores the material’s potential for advancing clean energy technologies and provides a foundation for further experimental and computational studies of 2D breathing Kagomé materials.