Researchers Illustrated the Morphology, Structure and Optical Properties of 3D Bi2O3 Hierarchical Architectures
2014-02-24
Bi2O3 is an extremely attractive material due to its unique features of large band gap, high dielectric permittivity, high refractive index, as well as marked photoluminescence and photo- conductivity, which have made it suitable for a wide range of applications such as gas sensors, optical coatings, capacitors, catalysts, photovoltaic cells, fuel cells and microwave integrated circuits. Nano-scale Bi2O3 with various morphologies, such as quantum dots, nanoparticles, nanowires, nanotubes, and nanofibers, have been fabricated because of the strong correlation between the spatial structure of nanomaterials and their attractive physicochemical properties.
Up to now, there are only a few reports on the synthesis of 3D Bi2O3 hierarchical architectures and all the methods reported for fabricating 3D Bi2O3 are carried out by acoprecipitation process with bismuth salt as the starting materials. Exploring new routes to large-scale synthesis of well-crystallized 3D Bi2O3 nanostructures is still a great challenge.
Therefore, researchers illustrated a facile approach of fabricating 3D Bi2O3 hierarchical architectures from electro deposited bismuth (Bi) film by using thermal oxidation in the air. 3D Bi2O3 hierarchical architectures were successfully fabricated from electro deposited Bi film by controlling the ramp rate and reaction temperature of thermal oxidation process.
Surface morphology observations showed that the 3D Bi2O3 hierarchical architectures exhibited flower-like architectures assembled by dozens of 2D nanoplates with a thickness of 25 nm. Characterizations of crystal structure revealed that the 2D nanoplates are well-crystallized β-Bi2O3. Furthermore, the 3D Bi2O3 hierarchical architectures exhibited a strong and wide photoluminescence (PL) signal in the range from 500 to 900 nm, with a maximum peak at 759 nm. Such unique architectures were expected to be utilized as next generation of nano-scale devices, such as sensors, optics and electronics. The result was published in Materials Letters in December 2013.