Bio-inspired construction of melanin-like polydopamine-coated CeO₂as a high-performance visible-light-driven photocatalyst for hydrogen production

In recent years, cerium oxide has been the most widely studied photocatalyst due to its unique properties. However, bare CeO₂shows poor photocatalytic performance under visible-light irradiation because it absorbs only UV light that leads to fast recombination of photogenerated electron-hole pairs. Therefore, surface modification can be one of the effective strategies to improve the visible-light absorption and reduce the recombination rate of photogenerated charge carriers. Herein, a series of CeO₂/polydopamine (CeO₂@PDA) composites were successfully fabricated by the polymerization of dopamine on the surface of CeO₂. Our results demonstrated that the surface modification of CeO₂by a small amount of PDA could effectively inhibit the photocatalytic reaction; this not only promoted the photoelectron injection and reduced the charge recombination rate, but also controlled the overgrowth of Pt cocatalyst. As compared to bare CeO₂, CeO₂@PDA shows remarkable photocatalytic hydrogen production performance. This composite also presents good durability and stability for the photocatalytic hydrogen production reaction. Thus, this study provides a new insight into the preparation of CeO₂composites with effective solar energy conversion.