Surfactant-assisted hydrothermal synthesis of Bi2O3 nano/microstructures with tunable size

A novel and simple citrate-assisted solution approach has been developed for the shape-selective synthesis of Bi2O3 nanostructures with controllable bandgaps and morphologies at a relatively low temperature of 40 °C. Different distinctive morphologies, including nanorods, nanoplates, plate-built cylinders, nanoplates with holes, and nanorings, are created due to the selective adsorption of the citrate molecules on certain faces during crystal growth. The bandgaps and aspect ratios of the Bi2O3 nanostructures are easily tuned by modifying the product morphologies by adjusting the amount of trisodium citrate. More novel and complex Bi2O3 nanostructures with controllable morphologies and sizes can be manufactured with our method by optimizing the experimental parameters. The distinctive nanostructures presented here extend the family of Bi2O3 nanostructures, and they also provide new opportunities for exploring the potential applications of Bi2O3 in a number of fields including photocatalysis, gas sensors, and photoelectrochemistry.