Different nanostructured In2O3 for photocatalytic decomposition of perfluorooctanoic acid (PFOA)

•In2O3 nanomaterials show much better activity than TiO2.•Photocatalytic half-life of PFOA was shortened to 5.3min.•Oxygen vacancies influence the activity for PFOA decomposition.•In2O3 porous microspheres, nanoplates and nanocubes were solvothermally synthesized. Perfluorooctanoic acid (PFOA), an emerging persistent organic pollutant, recently receives worldwide concerns including methods for its efficient decomposition. Three kinds of nanostructured In2O3 materials including porous microspheres, nanocubes and nanoplates were obtained by dehydration of the corresponding In(OH)3 nanostructures at 500°C for 2h. The In(OH)3 nanostructures with different morphologies were solvothermally synthesized by using different mixed solvents. As-obtained In2O3 nanomaterials showed great photocatalytic activity for PFOA decomposing. The decomposition rates of PFOA by different In2O3 materials, i.e. porous microspheres, nanoplates and nanocubes were 74.7, 41.9 and 17.3 times as fast as that by P25 TiO2, respectively. The In2O3 porous microspheres showed the highest activity, by which the half-life of PFOA was shortened to 5.3min. The roles of surface oxygen vacancies on the adsorption and photocatalytic decomposition of PFOA were discussed, and it was found that In2O3 materials with higher oxygen vacancy defects show better activity.