PdO/SnO(2) heterostructure for low-temperature detection of CO with fast response and recovery

In this paper, we developed a simple two-step route to prepare a PdO/SnO(2) heterostructure with the diameter of the SnO(2) and PdO nanoparticles at about 15 nm and 3 nm, respectively. In the evaluation temperature window between 80 °C and 340 °C, PdO/SnO(2) shows the best response to 100 ppm of CO at 100 °C with fast response time (14 s) and recovery time (8 s). Furthermore, the PdO/SnO(2) nanoparticles exhibit a low detection limit and good selectivity to CO against interfering gases as well as rarely-seen low-temperature stability and reversibility. Such enhanced gas sensing performance could be attributed to both the ultrafine structure of PdO and the synergy between PdO and SnO(2). The results clearly indicate the application of PdO/SnO(2) as a pratical low-temperature sensing material for CO.