Influence of La doping on the ethanol gas sensing properties of CdSnO₃ micro-cubes

Metal oxides with perovskite structure have draw much attentions in the field of gas sensors because of their easy component regulation by element doping, leading the improvement of gas sensing properties. Herein, La-doped CdSnO3 micro-cubes with excellent ethanol gas sensing properties were synthesized using a co-precipitation method combined with an annealing process. The phase structure, morphology, and micro-structure of pure CdSnO3 and La doped CdSnO3 micro-cubes were examined by X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscopy (TEM). The influence of La doping on the gas sensing performance of CdSnO3 were investigated. The sensor response of Cd0.88La0.12SnO3 toward 100 ppm ethanol reached 115.2 at the operating temperature of 300 oC, which was approximately 19 times higher than that of pure CdSnO3. In addition, Cd0.88La0.12SnO3 also showed fast response-recovery speed and good stability. The enhanced gas sensing properties of Cd0.88La0.12SnO3 micro-cubes were attributed to their abundant active sites, rich oxygen vacancy, and optimized internal electric field based on the analysis by X-ray photoelectron spectrometer (XPS), UV-Vis absorption characteristics (UV-vis), electron paramagnetic resonance (EPR), and ultraviolet photoelectron spectroscopy (UPS).