Enhancement of Z-Scheme Water Splitting Using Photocatalyst Sheets Fabricated by Simple Filtration of Long-Wavelength Visible-Light-Responsive Nonoxides and Carbon Nanotubes

Z-scheme water splitting was observed for photocatalyst sheets consisting of narrow-band-gap SrTaO2N (2.1 eV) and La5Ti2Cu0.9Ag0.1O7S5 (1.8 eV) immobilized by filtration of their suspension containing conductive carbon nanotubes. Preloading of carbon nanotubes on SrTaO2N and refinement of cocatalyst loading allowed the photocatalyst sheet to split water with an apparent quantum yield of 0.13% at 430 nm, which was superior to that reported for the photocatalyst sheet prepared by the particle transfer method using Au as the conductive material. The proposed method offers a facile, low-cost approach for the fabrication of photocatalyst sheets based on long-wavelength visible-light-responsive nonoxides for Z-scheme water splitting.