Rapid and Sensitive Carbon Monoxide Detection Using Novel SnO 2 /PEDOT-PSS Nanocomposite Gas Sensors

Abstract The development of reliable, rapid, and sensitive sensors for carbon monoxide (CO) detection remains critical due to the toxic and pervasive nature of this gas in industrial and urban environments. This study reports a novel gas sensing device based on a SnO₂PEDOT:PSS nanocomposite, fabricated via a simple sol-gel and solution mixing method. Comprehensive structural, morphological, and optical characterizations using XRD, FTIR, Raman, UV–Vis spectroscopy, and FE-SEM confirm the successful integration of crystalline SnO₂ nanoparticles within the PEDOT:PSS matrix. The sensor demonstrates markedly enhanced chemosensitivity to CO, with a maximum response of 114% at 300 ppm and a substantial improvement in response and recovery times (47 s and 44 s, respectively) compared to the pristine polymer. This enhancement is attributed to the synergistic effects between the semiconducting SnO₂ and the conductive PEDOT:PSS, which facilitate improved charge transfer and gas adsorption. Additionally, the sensor exhibits excellent selectivity towards CO over other gases and maintains stable performance over 50 days, underscoring its practical viability. These findings position the SnO₂/PEDOT:PSS nanocomposite as a promising material for next-generation, room-temperature CO sensing applications.