A sensitive SO2 gas sensor based on nanocellulose prepared tin dioxide under UV excitation.

Cellulose is a common natural polymer, and the surface of the nanocellulose has a large number of hydroxyl groups, which is possible used to precipitate metal salts to obtain the precursors, and then calcine to get the corresponding metal oxides. In this paper, tin dioxide (SnO2) nanoparticles were prepared with different amounts of nanocellulose by a low-temperature hydrothermal method (60°C) followed by calcination. The obtained material was verified to be impurity-free SnO2 nanoparticles by various types of physical phase analysis and morphological characterization. The SnO2 nanoparticles obtained from 50 mg nanocellulose exhibited a significantly improved sensing performance, and the response toward SO2 at 1 ppm was 4.68. In addition, multiple performance tests were conducted on the obtained gas sensor, and it was finally found to have a good gas sensitivity and an excellent selectivity. The repeatability and stability also presented preferable results. Additionally, the sensing mechanism was discussed. The prepared SnO2 sensor is promising for the detection of SO2 due to its high sensitivity and selectivity. [ABSTRACT FROM AUTHOR]