Low-energy consumption CuSCN-based ultra-low-ppb level ozone sensor, operating at room temperature

Abstract

Ozone (O3) is one of the main indoor as well as environmental air pollutant, thus its detection is of great importance. As a result, plenty of materials have been tested as O3 gas sensing elements, over the last fifty years. In this work, the gas sensing performance of Copper (I) Thiocyanate (CuSCN) powder against O3, is presented. The structure of CuSCN powder was polycrystalline as revealed by the X-Ray Diffraction technique, while by employing optical absorption measurement the direct and indirect energy band gaps were calculated and found to be 3.72 eV and 3.48 eV, respectively. CuSCN powder was tested against O3 at different concentrations, showing a low detection limit of 15 ppb with a response of 1.06, at room temperature (25 °C), applying a very low input voltage of 0.1 V. Moreover, the corresponding response and recovery times were 137.4 s and 111 s, respectively, while it can successfully distinguish the different ozone concentrations in less than 20 s. The above-mentioned values make CuSCN a possible candidate material for ultra-low O3 concentration detection, at room temperature, with low-energy consumption.