Transparent gas senor and photodetector based on Al doped ZnO nanowires synthesized on glass substrate

In this work high density, well-aligned Al doped ZnO (AZO) nanowires are hydrothermally synthesized on glass substrate at 99 °C. The Al content is ~1.57 at%. The PL spectrum shows that Al impurities caused an increase in the number of oxygen vacancies. The spectral response results show that the maximum responsivity and quantum efficiencies η of AZO NWs are 3.61 A/W and 84.9%, at an incident light wavelength of 360 nm. These AZO NWs have less humidity sensitivity, thus decreasing the effect of humidity effect on gas sensing. Low gas concentrations of 10 ppm ethanol and 10 ppm acetone can be detected with good responses of 24.5% and 21.2%, using the AZO NW sensor at 200 °C and with 0.1 V applied bias.