Sodium alginate assisted construction of ZnSnO ₃ microspheres enhanced HCHO sensing performance under UV illumination at room temperature

Abstract

The ZnSnO 3 microspheres were fabricated with water-soluble biopolymer sodium alginate (SA) as a crystal growth modifier under hydrothermal conditions. The gas-sensing properties of ZnSnO 3 @SA were tested under the illumination of UV light at room temperature. The results showed that the ZnSnO 3 @SA sensor exhibited better HCHO gas response than pristine ZnSnO 3 sensor, which was ascribed to the introduction of SA that changed the size distribution of the microspheres. Test results of HCHO gas with different concentrations indicated that the ZnSnO 3 @SA sensor had a good linearity. This approach would provide a potential route for the HCHO sensor to work at room temperature. In addition, the sensing mechanism was also discussed.