Facile fabrication and enhanced gas sensing properties of In2O3 nanoparticles

Nanoscale single crystalline In2O3 nanoparticles with sizes of 10-40 nm are prepared by annealing gas-liquid phase chemical deposition-synthesized In2S3 nanoparticles and are developed for the detection of acetone gas. The In2O3 nanoparticles are characterized by TEM, HRTEM, SAED, EDX and XRD. Moreover, the products are further studied by room temperature UV-absorption and photoluminescence (PL) spectroscopy. To demonstrate the usage of such nanoparticles, gas sensors based on the as-synthesized In2O3 nanoparticles are fabricated and exhibit good selectivity, high sensitivity, rapid response, a low concentration detection limit and better repeatability towards acetone gas at a relatively low operating temperature. Such excellent gas sensing performances are attributed to small crystal sizes and the existence of abundant oxygen vacancies. As demonstrated, the single crystalline In2O3 nanoparticles are highly promising for real-time monitoring gas sensor applications.