Self-assembled 3D BiOCl hierarchitectures: tunable synthesis and characterization

3D hierarchitectures (HAs) of BiOCl composed of 2D nanosheets, which intercross with each other, have been successfully synthesized by a template-free solvothermal method at 160 °C for 12 h. The morphology and compositional characteristics of the 3D HAs were investigated by various techniques. On the basis of characterization results, the growth of such 3D HAs has been proposed as an Ostwald ripening process followed by self-assembly. The growth and self-assembly of BiOCl nanosheets could be readily tuned with the molar ratio of urea to BiCl3·5H2O, which brought different morphologies and microstructures to the final products. The specific surface area and porosity of the 3D hierarchitectured (HAd) BiOCl also were investigated by using nitrogen adsorption and desorption isotherms. UV–vis spectra reveal that the band gap energies of the 3D HAs can be tuned from 3.05 eV to 3.32 eV. The as-prepared 3D HAd BiOCl showed much higher photocatalytic activity than that of the reported in the literature, which was evaluated by the degradation of Rhodamine-B (RhB) dye under ultraviolet light irradiation.