A novel hetero-structure sensor based on Au/Mg-doped Tio(2)/SnO2 nanosheets directly grown on Al2O3 ceramic tubes

作者：Xu, Hongyan; Ju, Dianxing; Chen, Zhengrun; Han, Rui; Zhai, Ting; Yu, Huanqin; Liu, Caiyun; Wu, Xiangwen; Wang, Jieqiang; Cao, Bingqiang^*

来源：Sensors and Actuators B: Chemical , 2018, 273: 328-335.

DOI：10.1016/j.snb.2018.06.055

• Au/Mg-doped TiO2/SnO(2)nanosheets
• Schottky contact
• n-n Heterojunction
• Gas sensor

D Chemiresistive gas sensors with novel nanostructures, high response and reliable fabrication process have been fabricated successfully by designing Au/Mg-doped TiO2/SnO2 nanosheets hetero-structures. Mg doping was used to decrease the work function of TiO2, which can lead to the electrons in TiO2 greatly depleted due to the formation of Schottky contact and n-n heterojunction. SnO2 nanosheets were directly grown on Al2O3 tube with a cost-effective hydrothermal process. By employing pulsed laser deposition (PLD) and direct current sputtering methods, the construction of gold (Au) nanoparticles-loaded Mg-doped TiO2/SnO2 heterostructure is highly controllable and reproducible. In comparison with pristine SnO2 and TiO2/SnO2, Mg-doped TiO2/SnO2 sensors exhibit high response (30.4) and short response time (9 s) to 50 ppm TEA gas, which is about 6 times higher than pure SnO2 sensor and 2 times higher than TiO2/SnO2 sensor at a working temperature of 260 degrees C. The mechanism for sensing property enhancing of the Au/Mg-doped TiO2/SnO2 sensor was also discussed in detail with the semiconductor depletion layer model introduced by Au-TiO2 Schottky contact and TiO2/SnO2 n-n heterojunction.

• 出版日期2018-11-10
• 单位山东师范大学; 济南大学