Gas sensing selectivity of oxygen-regulated SnO2 films with different microstructure and texture

• DOI: 10.1016/j.jmst.2019.06.005
• Publication Date: 2019-06-21T17:08:16Z
• Authors: Ruiwu Li; Yanwen Zhou; Maolin Sun; Zhen Gong; Yuanyuan Guo; Xitao Yin; Fayu Wu; Wutong Ding
• Keywords: 01 natural sciences; 0104 chemical sciences

Abstract The selectivity of gas sensing materials is increasingly important for their applications. The oxygen-regulated SnO2 films with (110) and (101) preferred orientation were obtained through magnetron sputtering, followed by annealing treatment. Their micro-structure, surface morphology and gas response were investigated by advanced structural characterization and property measurement. The results showed that the as-prepared (110)-oriented SnO2 film was oxygen-rich and had more adsorption sites while the as-prepared (101)-oriented SnO2 film was oxygen-poor and more sensitive to de-oxidation. H2 gas sensitivity, response speed, selectivity between H2 and CO of the (110)-orientated SnO2 film was superior to that of the (101)-orientated SnO2 film. After treated at high temperature and high vacuum, the reduction of gas-sensing properties of the annealed (110) SnO2 film was much more than that of the annealed (101) SnO2 film. The lattice oxygen was responsible for the difference in gas-sensing response between (110) and (101)-oriented SnO2 films under oxygen regulation. This work indicated the gas-sensing selectivity of the different crystal planes in SnO2 film, providing a significant reference for design and extension of the related materials.