Low Temperature Ammonia Sensor Based on Cataluminescence on Nano-Ti2W3O13
A novel gas sensor based on cataluminescence (CTL) on the surface of nanosized Ti2W3O13 was demonstrated for direct determination of ammonia in air. Trace ammonia was firstly absorbed on active carbon at room temperature to concentrate, then desorbed at 105°C to determine. The sensor showed high selectivity to ammonia at wavelength of 540 nm, satisfying activity at temperature of 180°C and good stability at air carrier flow rate of 120 ml/min. The linear range of CTL intensity versus concentration of ammonia was 0.8∼70 mg/m3 (γ=0.9991), and the detection limit (3σ) was 0.5 mg/m3. The recovery of artificial sample was 97.4%—102.5% by this method. There was no response to benzene, SO2, CO, ethanol and formaldehyde. This sensor allows on-line monitoring of ammonia in air.
