SnO2 doped NiO heterostructure nanofibers prepared by electrostatic spinning: A novel sensor for catalytic oxidation of formaldehyde

Up to now, there were a large number of literatures on the detection of gaseous formaldehyde (HCHO), however the liquid HCHO, which had the same harmfulness as gaseous HCHO, was rarely paid attention to by people. In this work, the electrospinning nanomaterial preparation process was used to fabricate the liquid HCHO electrochemical sensor. Firstly, five different sets of electrode materials were set up, and the material with the best results (SnO2/NiO NFs (No. 3)) was tested by scanning electron microscopy (SEM), X-ray diffraction (XRD), cyclic voltammetry (CV), and electrochemical frequency impedance (EIS). Then the detection principle of the electrochemical sensor and the electrode reaction process of catalytic oxidation of HCHO were analyzed. Finally, the limit of detection (LOD), detection range, selectivity, and stability of the SnO2/NiO NFs (No.3) for the catalytic oxidation reaction of HCHO were analyzed by CV and potential polarization methods.