Band-Gap Control of Zinc Sulfide: Towards an Efficient Visible-Light-Sensitive Photocatalyst.

The electronic properties of transition-metal-doped zinc sulfide (ZnS) have been investigated by using first-principles calculations. Transition-metal doping can allow electronic transitions at energies corresponding to visible-light wavelengths, thus potentially resulting in increased photocatalytic efficiency under sunlight. In particular, our calculations show that transition-metal atoms that produce little lattice strain, such as Co, Ni, Mn, and Fe, can be readily incorporated in ZnS. Due to their low formation energies and appropriate band energies, we predict that Ni- and Co-doped ZnS will be promising materials for photocatalytic hydrogen production.