Visible light activated tungsten oxide sensors for NO_2 detection at room temperature

摘要

The sensing characteristics of tungsten oxide (WO_3) gas sensors under visible light illumination have been investigated at room temperature. Sensing measurements were performed on sputtered (thin-film) and screen-printed (thick film) WO_3 layers towards sub-ppm NO_2. Light sources with different wavelength were employed to illuminate the WO_3 sensors. The results showed that the light illumination effectively improved the NO_2 sensing properties and the 475 nm light (blue colour) was the most effective for the WO_3 sensors.