Coaxial electrospinning route to prepare Au-loading SnO2 hollow microtubes for non-enzymatic detection of H2O2

Au-loading SnO2 hollow microtubes (Au-SnO2-MTs) have been successfully prepared by the coaxial electrospinning method, where the sol solution containing poly-vinylpyrrolidone and metal salts were used as outer solution and paraffin was used as inner solution, respectively. The combined characterizations of scanning electron microscopy and X-ray diffraction indicating the successful preparation of Au-SnO2-MTs with the diameter of MTs about 500-600 nm, and the thickness of the hollow MTs about 70-80 nm. It is also found that the Au-SnO2-MTs exhibit catalytic activity for electrochemical reduction of H2O2, leading to a non-enzymatic H2O2 sensor. The H2O2 sensor thus obtained shows the linear detection range from 10 μM to 1 mM (r = 0.997), and the detection limit about 0.60 μM at a signal-to-noise ratio of 3. Furthermore, the H2O2 sensor also exhibits excellent selectivity for H2O2 in comparison to other normally co-existing electroactive species (such as dopamine, ascorbic acid, uric acid and glucose) and inorganic anions.