Preparation of Ce-doped CdS nanomaterials and mechanism study on their enhanced gas-sensing performance toward n-butanol

First report of Ce-doped CdS nanomaterials as n-butanol sensors. • Sensor exhibits a maximum response value of 224.2 at 50 ppm n-butanol. • Sensor demonstrates extremely fast response/recovery times for n-butanol. • Sensor exhibits excellent selectivity toward n-butanol. • Possesses outstanding long-term stability. Ce-doped CdS nanomaterials were successfully synthesized by a hydrothermal method. Various characterization techniques confirmed the successful substitution of Cd sites in the CdS lattice by Ce ions. Gas-sensing tests demonstrated that at an optimal Ce doping level of 1 at%, the sensor exhibited an outstanding response of 224.2–50 ppm n-butanol at 175 ℃, which is approximately 3.5 times higher than that of pristine CdS. Meanwhile, it displayed excellent response/recovery characteristics (14 s/10 s). Furthermore, the sensor showed superior selectivity toward n-butanol, with a negligible response to benzene gas. Mechanism analysis revealed that the abundant sulfur vacancies induced by Ce doping, along with the multivalent redox catalytic effect of Ce ions, are the key factors contributing to the significant enhancement of gas-sensing performance. Download: Download high-res image (142KB) Download: Download full-size image