Mesoporous In2O3 nanocubes were synthesized through a simple, low-cost hydrothermal method without using soft template, followed by calcination. The morphology and crystal structure of the In2O3 nanocubes were examined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The gas sensors were fabricated by drop casting method and tested over flammable and explosive H2 gas at different temperatures. The best performance was found at working temperature of 350oC with the highest response of 2.3 to 1000 ppm H2. The sensor showed fast response/recovery time (5 s / 45 s), and good stability after six consecutive measurement cycles.
