A Direct Z-Scheme for the Photocatalytic Hydrogen Production from a Water Ethanol Mixture on CoTiO₃/TiO₂ Heterostructures

Photocatalytic H2 evolution from ethanol dehydrogenation is a convenient strategy to store solar energy in highly valuable fuel with potential zero net CO2 balance. Herein, we report on the synthesis of CoTiO3/TiO2 composite catalysts controlled amounts distributed CoTiO3 nanodomains for photocatalytic dehydrogenation. We demonstrate these materials provide outstanding hydrogen rates under UV and visible illumination. The origin this enhanced activity extensively analyzed. In contrast previous assumptions, UV–vis absorption spectra ultraviolet photoelectron spectroscopy (UPS) prove heterostructures have type II band alignment, conduction minimum below H2/H+ level. Additional steady-state photoluminescence (PL) spectra, time-resolved PL (TRPLS), electrochemical characterization such result enlarged lifetimes photogenerated charge carriers. These experimental evidence point toward direct Z-scheme as mechanism enabling high composites addition, probe small changes temperature strongly modify tested, which could be used further promote performance thermophotocatalytic reactor.