Interfacial-engineered CoTiO3-based composite for photocatalytic applications: a review

Photocatalysis is a green chemical process that could partly solve energy and pollution issues. Catalysts such as cobalt titanate, CoTiO3, have intrigued scientists due to a visible light-responsive band gap of about 2.3 eV and a high valance band potential of about 2.35 eV that allow a remarkable oxidative activity. Nonetheless, CoTiO3 photocatalytic activity is limited by charge recombination, thus requiring modifications. For instance, the introduction of a second semiconductor allows improved charge separation and notable enhancement of the activity. Here we review interfacial engineering of CoTiO3 by introduction of a second semiconductor. We describe the synthesis and photocatalytic applications of bare and modified CoTiO3. Modified CoTiO3 composites are categorized into Type-I, Type-II, Z-scheme, and S-scheme heterojunctions, depending on the band structures of the composite.