Highly sensitive MXene-based SO₂ sensor enhanced by modification of SnO₂ at room temperature

High-performance and room-temperature gas sensors are ideal for industrial production and environmental detection. Enhancing gas-detection capability by the use of highly conductive MXene in conjunction with metal oxide materials is a potential approach. In this work, we have prepared a gas-sensing composite device based on SnO₂/V₂CT_x nanocomposites, which can be used to detect the concentration of SO₂ gas at room temperature (~ 20 ℃). This paper modified two-dimensional (2D) V₂CT_x MXene with SnO₂ nanoparticles by electrostatic binding method to synthesize SnO₂/V₂CT_x composite nanomaterials. The experimental results show that at room temperature, the addition of SnO₂ nanoparticles can markedly improve the gas-sensing response (from 66 to 83%) characteristics of pure V₂CT_x to SO₂. The gas sensitivity of SnO₂/V₂CT_x MXene nanocomposites can reach 83%, and its response/recovery time is 98 s/81 s under 10 ppm SO₂. The gas-sensing composite devices made of SnO₂/V₂CT_x composite nanomaterials also show good selectivity and application prospects.