Controlled fabrication and optical properties of 3D hierarchical α-Bi2O3 siamesed microflowers

Three dimensional (3D) hierarchical α-Bi2O3 siamesed microflowers have been synthesized by a glycerin-assisted hydrothermal method. The microflowers of 30 μm were built up of oblique prism-like nanorobs, with mean width of 300 nm and thickness of 100 nm. In the hydrothermal process, hierarchical microstructures constructed by nanoribbons, ultrathin nanoflakes and oblique prism-like nanorobs can be found at different step of crystal growth. Morphology evolution of α-Bi2O3 was analyzed and the probable formation mechanism was proposed based on experimental results. The vibrational properties, optical absorption and photoluminescence (PL) characteristics of the sample were investigated.