Strain engineering and photocatalytic application of single-layer ReS2

We present a theoretical study on the electronic, dynamical, and photocatalytic properties of single-layer ReS2 under uniaxial and shear strains. The single-layer ReS2 shows strong anisotropic responses to straining. It remains dynamically stable for a wide range of x-axial strain, but becomes unstable for 2% y-axial compressive strain. The single-layer ReS2 is calculated to be an indirect bandgap semiconductor, and there is an indirect−direct bandgap transition under 1–5% x-axial tensile straining. The single-layer ReS2 is predicted incapable of catalyzing the water oxidation reaction. However, 1–5% y-axial tensile strain can enable the single-layer ReS2 for overall photocatalytic water splitting. Besides, the single-layer ReS2 can also catalyze the overall water splitting and be most efficient under acidic water solutions with pH = 3.8.