Microsized BiOCl Square Nanosheets as Ultraviolet Photodetectors and Photocatalysts.

BiOCl microstructures that include microspheres stacked by nanosheet and microsized square nanosheets, with a large lateral size of 3-5 μm and a thickness of 35 nm (the side length/thickness ratio is ∼100), are synthesized by a solvothermal method with the assistance of polyvinylpyrrolidone. The exposed face of the large square nanosheet is {001} facet. The BiOCl microstructures show good photocatalytic activity toward decomposition of Rhodamine B under ultraviolet-visible light irradiation. Moreover, individual microsized BiOCl square nanosheets are employed as the building block for construction of an ultraviolet photodetector. Because of its large size, thin thickness, and high surface-to-volume ratio, a BiOCl nanosheet shows high sensitivity and fast transient response to ultraviolet light in the spectral range 200-380 nm.