Highly Sensitive and Selective Room-Temperature NO2 Gas Sensor With Ce2Sn2O7/g-C3N4 Nanocomposite

Abstract

In this study, we have fabricated a highly sensitive and selective room-temperature nitrogen dioxide (NO2) gas sensor based on a novel composite (Ce2Sn2O7 /g-C3N4) prepared by a facile hydrothermal method. The fabricated Ceg1 sensor exhibits outstanding sensing performance at room temperature ( $28~^{\circ }$ C) and highly responds ( ${R} =6.57$ ) toward 10 ppm of NO2. The fabricated Ceg1 sensor displays a superior selectivity toward NO2 gas molecules compared to various gas molecules and reflects the quick response time of 7 s toward the 10 ppm of NO2 gas molecules. Moreover, the Ceg1 sensor preserved 89% of its response for 60 days, exhibiting outstanding stability. Additionally, the Ceg1 sensor showed the ultralow detection limit of 48 ppt. The exceptional performance is attributed to the novel interface between Ce2Sn2O7 and g-C3N4, combined with the novel combination’s high specific surface area and oxygen vacancies. This novel method not only boosts the performance of NO2 detection but also significantly contributes to the advancement of gas sensors critical for environmental monitoring and protecting human health.