Molecular layer deposition of charge-transfer complex thin films with visible-light absorption

A titanium-aryloxide (Ti-Ao) complex showing high visible-light absorption was fabricated by molecular layer deposition. Studies using ultraviolet–visible spectroscopy and density functional theory calculations revealed that the origin of the visible absorption was ligand-to-metal charge-transfer. ZnO/Ti-Ao nanolaminate phototransistors functioned synergistically with Ti-Ao acting as a visible-light absorber, and ZnO serving as a good semiconductor.