Visible-light-enhanced gas sensing of CdSxSe1-x, nanoribbons for acetic acid at room temperature

The visible-light-induced gas sensors based on the ternary compound CdSxSe1-x nanoribbons have been successfully fabricated. The compound was obtained via a metal-catalyzed physical evaporation route. X-ray diffraction, scanning electron microscopy and transmission electron microscopy were employed to confirm the formation and composition of CdSxSe1-x, nanoribbons. The optimum operating temperature of CdSxSe1-x-based gas sensors in the dark is 200 degrees C when they were used in detection of acetic acid with the concentration range from 25 to 400 ppm, while the optimum operating temperature could be reduced by approximately 100 degrees C under visible light irradiation. More importantly, the sensors can even work efficiently at room temperature under visible light. The calculated limit of detection decreased from 1.13 ppm (200 degrees C, dark) to 0.87 ppm (100 degrees C, visible light) and 1.03 ppm (room temperature, visible light), respectively. The enhanced sensing properties of the CdSxSe1-x-based gas sensors were due to photo-generated electrons. This work will pave a way for the development of the low-cost practical gas sensors. (C) 2015 Elsevier B.V. All rights reserved.