Ordered mesoporous In-(TiO2/WO3) nanohybrid: An ultrasensitive n-butanol sensor

Indium doped 2-D mesoporous (TiO2/WO3) nanohybrids possessing large intrinsic surface area and ordered pore channels were synthesized using mesoporous silica, SBA-15 as hard template through a simple nanocasting strategy. The TiO2/WO3 was synthesized as a result of negative replica of SBA-15 template during nanocasting process, which was further modified with Indium nanoparticles using wet impregnation technique. The nanohybrids were tested against the detection of important indoor flammable organic pollutants including n-butanol, toluene, benzene, xylene, 2-propanol and ethyl acetate. The sensing results illustrate that 1 wt% In-doped in TiO2/WO3 shows 2.65 times better response (R = 127.2 @ 200 degrees C) to 50 ppm n-butanol gas than pure TiO2/WO3 (R = 48 @ 210 degrees C) nanocomposite at relatively lower operating temperature. A fast response time (2.2 s), rapid recovery time (3 s), linear response, high stability and excellent selectivity were observed for the developed nanohybrid sensor. It is expected that the promising findings reported in this study can be extended to synthesize ordered mesoporous nanostructures which will be useful for the design and construction of futuristic e-nose with enhanced gas-sensing performance. (C) 2016 Elsevier B.V. All rights reserved.