Template-free synthesis of In2O3 nanoparticles and their acetone sensing properties

Ordered In2O3 nanoparticles (In2O3 NPs) were successfully prepared via a template-free method. The synthesis was conducted in a water-glycerol-ethylene glycol mixed solvent without any templates, and the ultra-fine nanostructured In2O3 has a uniform size of about 20-30 nm. The In2O3 nanoparticles exhibited improved sensitivity, fast response, and high selectivity to acetone. The enhanced acetone performance results from a large surface area with enough sensing active sites, and small particle size for effective electron depletion.