Photocatalytic Reduction on Bismuth-Based p-Block Semiconductors

With the constant increase in demand for fuel energy, research on the exploration of renewable energy sources is becoming significantly critical. Herein, photocatalysis for the direct conversion of solar to chemical energy has attracted tremendous attention. In particular, because of the energy band edges mainly formed by p orbitals or s-p hybridized states, resulting in narrow band gaps and highly dispersive band structures, photocatalysts constructed from p-block elements exhibit remarkable visible-light photocatalytic activity. Taking bismuth oxyhalide-based photocatalysts, a typical family of p-block semiconductors, as an example, the following perspective mainly focuses on three significant strategies, including constituent adjustment, vacancy engineering, and the construction of heterostructures, on the design and construction of bismuth-based solar-conversion systems with high efficiencies in terms of H₂ evolution, CO₂ reduction, and N₂ fixation. Finally, our thoughts on future challenges to be overcome for the development of advanced photoreduction systems are presented.