The {0 0 1} facets-dependent superior photocatalytic activities of BiOCl nanosheets under visible light irradiation

Graphical abstract: - Highlights: • BiOCl nanosheets were selectively synthesized via a facile hydrothermal method. • The percentage of {0 0 1} facets over BiOCl nanosheets were well controlled. • These samples manifest superior catalytic activity for the degradation of RhB dyes. - Abstract: BiOCl nanosheets with tunable lamella thickness and dominantly exposed {0 0 1} facets were selectively synthesized via a facile hydrothermal method. By modifying the synthetic parameters, such as the amount of P123 and mannitol, the reaction time, types of surfactants, the size, thickness, morphologies, and percentage of {0 0 1} facets over BiOCl nanosheets were well controlled. The exposed {0 0 1} facets with high surface energy and high density of oxygen atoms are not only conducive to the adsorption of the rhodamine B (RhB) dye but also can accumulate the photo-generated electrons, which can be captured by O₂ and converted into reactive oxygen species O₂⁻·. Therefore, the resultant ultrathin BiOCl nanosheets with exposed {0 0 1} facets exhibit superior catalytic activity for dye photosensitization degradation under visible light irradiation. Impressively, the ultrathin BiOCl nanosheets prepared with P123 and mannitol manifest superior catalytic activity and RhB was completely degraded within 20 min. Our current work is expected to offer a new insight into photocatalytic theory for better understanding of visible light photocatalytic reactions and rational design of highly active photocatalysts