The structure and photoluminescence of Bi4Ti3O12 nanoplates synthesized by hydrothermal method

Bismuth titanate (Bi4Ti3O12) nanoplates were synthesized by polyethylene glycol-assisted hydrothermal method at 200 °C. The as-prepared samples were investigated by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy and the room-temperature photoluminescence. The Bi4Ti3O12 nanoplates are single crystalline and orthorhombic perovskite structure with the average rim sizes of about 200 nm and thickness of 10–20 nm. One blue–green photoluminescence band centered at around 470.4 nm was observed at room temperature. The investigation of the effects of the annealing temperatures on room-temperature visible emission showed that the annealing temperatures or grain size play important roles for the intensities of blue–green light emission, and the oxygen vacancies should be responsible for this emission.