Sensors for the nitrogen oxides, NO2, NO and N2O, based on In2O3 and WO3 nanowires |
| |
Authors: | CS Rout K Ganesh A Govindaraj CNR Rao |
| |
Institution: | (1) Chemistry and Physics of Materials Unit, DST Unit on Nanoscience and CSIR Centre of Excellence in Chemistry, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore, 5600 64, India |
| |
Abstract: | Sensing characteristics of ZnO, In2O3 and WO3 nanowires have been investigated for the three nitrogen oxides, NO2, NO and N2O. In2O3 nanowires of ∼20 nm diameter prepared by using porous alumina membranes are found to have a sensitivity (defined as the ratio of the sensor resistance in the gas concerned to that in air) of about 60 for 10 ppm of all the three gases at a relatively low temperature of 150 °C. The response and recovery times are around 20 s. The sensitivity of these In2O3 nanowires is around 40 for 0.1 ppm of NO2 and N2O at 150 °C. WO3 nanowires of 5–15 nm diameter, prepared by the solvothermal process show a sensitivity of 20–25 for 10 ppm of the three nitrogen oxides at 250 °C. The response and recovery times are 10 s and 60 s, respectively. The sensitivity is around 10 for 0.1 ppm of NO2 at 250 °C. The sensitivity of In2O3 and WO3 nanowires is not affected by humidity even up to 90% relative humidity. The study also reveals that the sensing mechanism for the three nitrogen oxides have a commonality in that the desorption of oxygen is a crucial step in all the cases. PACS 07.07.Df; 85.35.-p; 82.35.Np |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|