Microparticles of α-Bi2O3Obtained from Bismuth Basic Nitrate [Bi6O6(OH)2(NO3)4•2H2O] with Photocatalytic Properties

Alpha phase bismuth oxide (alpha-Bi2O3) microparticles were prepared through the annealing at 600 degrees C of basic bismuth nitrate [Bi6O6(OH)(2)(NO3)(4)center dot 2H(2)O] precursors with different morphologies and crystallinity that were obtained by a chemical precipitation method. The precursors were synthesized using ethylenediamine (EN) solvent and varying the HNO3/Bi(3+)and HNO3/EN molar ratios, with and without thermal reflux. The influence of the HNO3/EN molar ratio and the thermal reflux on the physicochemical properties of the Bi6O6(OH)(2)(NO3)(4)center dot 2H(2)O precursors and the obtained alpha-Bi(2)O(3)phase were analyzed by X-ray diffraction, thermogravimetric and differential scanning calorimetric analysis, FTIR analysis, scanning electron microscopy and diffuse reflectance spectroscopy. A correlation between the chemical composition of the Bi6O6(OH)(2)(NO3)(4)center dot 2H(2)O precursors and the physicochemical properties of alpha-Bi(2)O(3)phase was proposed. Finally, the photocatalytic activity of the alpha-Bi(2)O(3)microparticles was tested in the photodegradation of indigo carmine dye under UV-A light.

Automated summary

The study prepared alpha phase bismuth oxide microparticles through a chemical precipitation method, analyzing the effects of different synthesis conditions on their physicochemical properties and photocatalytic activity.