Visible light induced super-hydrophilicity on single crystalline TiO2 nanoparticles and WO3 layered thin films

Single crystalline nitrogen and sulfur doped anatase octahedral TiO2nanoparticles were synthesized from titanate nanotubes. The surfaces of these octahedral nanoparticles were oriented to the (101) face. These particles were highly dispersed in water, and thin films were coated by spin-coating of colloidal solution. These films had a (101) orientation to the substrates. Thin films of these nanoparticles on a WO3 layer exhibited a super-hydrophilic conversion under 0.2 mW cm−2 visible light illumination.