Facile fabrication and optical property of β-Bi₂O₃ with novel porous nanoring and nanoplate superstructures

Novel β-Bi₂O₃ crystals with nanoring and nanoplate surperstructures, which are composed of porous nanoparticles with mean pore diameter of 8 nm, were produced via a facile soft chemistry route of solvent refluxing technique. Most of the rings have the average inner diameter of 200 nm and the mean rim thickness of 20 nm. Photoluminescence spectra of the nanorings at room temperature were investigated, which demonstrated that the rings presented excellent optical properties. The influence of aging time on the morphology and structure of β-Bi₂O₃ superstructures was also studied, indicating that the nanoring superstructures transformed into nanoplates after a long aging time. The formation mechanism of the β-Bi₂O₃ superstructures was also explored. This approach will be further extended to solvent-controlled fabrication of related oxides with novel complex superstructures.