Ethanol Gas Sensors With Nanocomposite of Nickel Oxide and Tungsten Oxide

Different nanostructures of tungsten oxide (WO3) can be hydrothermally synthesized by controlling the pH value through adding HCl solution. WO3 has a square plate-like structure when the mixture solution has a pH value of 1.0. At this pH, WO3 nanoplates are dispersed and did not formed clusters. Porous nickel oxide (NiO) spheres are also hydrothermally synthesized for decoration on the surface of WO3 nanoplates. Holes on the NiO spheres increase the surface area of the material and enhance the sensing performances of the sensor. By combining these two materials, the sensor with p-n-n junction is sensitive to ethanol and has a high sensitivity of 155%. The response and recovery times are also fast with good sensitivity and selectivity. It has a high potential for applying to ethanol sensing in industrial and medical areas.

Automated summary

By controlling the pH value, different nanostructures of tungsten oxide can be synthesized hydrothermally, while decorating porous nickel oxide spheres on the surface of tungsten oxide nanoplates to enhance the sensor's performance. The sensor with p-n-n junction shows high sensitivity to ethanol, fast response and recovery times, and is suitable for ethanol sensing in industrial and medical areas.