Synthesis of In2O3 nanoparticles via a green and solvent-free method

A green method for the synthesis of indium oxide (In 2 O 3 ) nanoparticles is described in this study. Nanoparticles are formed after simple grind and bake of the mixture of indium nitrate and ammonium bicarbonate. The influences of ratios of reactants and annealing atmosphere on the structure, optical properties and morphology of In 2 O 3 nanoparticles are also investigated. A blue and red shift of optical absorption were observed by using the different ratios of reactants and annealing atmosphere, respectively. This is attributed to the variation of particle size and concentration of oxygen vacancy of In 2 O 3 nanoparticles.