Interfacial Electronic States of GeC/g‐C₃N₄ van der Waal Heterostructure with Promising Photocatalytic Activity via Hydrogenation

Abstract

We systematically examine the impact of hydrogenation on the optical and electronic characteristics of GeC/g−C3N4 vdWHs with four different stacking patterns using first−principles calculations. The phonon spectra, interlayer distance, binding energies and AIMD calculations show the kinetic, mechanical and thermal stability of GeC/g−C3N4 vdWH after hydrogenation at 300, 500 and 800 K and also possesses anisotropic Poisson’s ratio, Young’s and bulk modulus, suggesting that it’s a promising candidate for experimental fabrication. GeC/g−C3N4 vdWH has a bandgap of 1.28 eV, but hydrogenation dramatically increases it to 2.47 eV. As a result of interface‐induced electronic doping, the electronic states in g−C3N4 might be significantly adjusted by coming into contact with hydrogenated GeC sheets. The vdWH exhibits a type‐II semiconductor, which can enhance the spatial separation of electron‐hole pairs and has a strong red−shift of absorption coefficient than those of the constituent monolayers. The high potential drop caused by the significant valence and conduction band offsets effectively separated the charge carriers. The absorption coefficient of GeCH2/g−C3N4 vdWH is highly influenced by biaxial compressive strain. Our theoretical research implies that the hydrogenated GeCH2/g−C3N4 vdWH possesses tunable optical and electronic behaviour for use as a hole‐transport material in solar energy harvesting, nanoelectronic and optoelectronic devices.