Facile hydrothermal synthesis of nanobricks assembled WO3 microflowers and their ethanol sensing properties

In this work efforts are made to explore the amount and effect of complexing surfactants to fabricate ethanol sensor using thick films of tungsten oxide (WO3). The hierarchical architectures of WO3 microflowers were synthesized by a facile hydrothermal method using potassium sulfate (K2SO4) and oxalic acid (C2H2O4). The microflower with 3-7 μm diameter comprises of nanobricks and nanosheets- like hierarchical morphology with their thickness ranging from 30 to 100 nm. The sensor achieves its maximum sensitivity of 72% towards 1 ppm of ethanol vapor at the optimal operating temperature of 250 °C The sensor shows good selectivity towards ethanol.