A Highly Selective and Fast-Responding Hydrogen Sensor based on In2O3 Nanocubes

Abstract

Abstract:The In 2 O 3 nanocubeswere successfully synthesized without any templates by calcining the In(OH) 3 precursor in air at 300 o C for 2 h and their H 2 sensing characteristics were investigated. The In(OH) 3 precursor was prepared through a wet chemical route at room temperature (27 o C)using InCl 3 ,4H 2 O and NH 4 OHas starting materials.The formation ofIn 2 O 3 nanocubes was confirmed by X-ray diffraction measurement (XRD), X-ray photoelectron spectroscopy (XPS)and transmission electron microscopy (TEM)analysis.The In 2 O 3 nanocubes exhibit excellentH 2 sensing properties such as, high gas response (~130 to 50 ppm H 2 at 325 o C), extremely rapid response (1s), fast recovery (4-5 s), excellent repeatability and good selectivity. Furthermore, the lower detection limit is ~3.87 ppm, which is lower than the permissible explosive limit for H 2 . The experimental results demonstrate the potential of theIn 2 O 3 nanocubes as sensing material in the fabrication of hydrogen sensors.