Pure SnO₂ and La-doped SnO₂ nanocomposite were prepared through hydrothermal method, and their gas sensing performances were studied. Results indicate that the sensing response of the 5 wt% La-doped SnO₂ nanocomposite reached 29.5 when exposed to 75 ppm methanol at the optimal operating temperature of 220 °C, which was over seven times larger than that of pure SnO₂ nanoparticles. In addition, the response and recovery time were shortened to 12 s and 7 s, respectively. Moreover, the 5 wt% La-doped SnO₂ nanocomposite presents a good selectivity toward methanol among methanal, methanol, ammonia, acetone and benzene gases. The improvement in the gas sensing properties of the 5 wt% La-doped SnO₂ nanocomposite toward methanol can be attributed to the smaller crystallite size, larger surface area and the modified chemical nature of nanocomposite surface.

中文翻译：

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基于La掺杂SnO 2传感器的甲醇高灵敏度高选择性检测

采用水热法制备了纯SnO ₂和掺La的SnO ₂纳米复合材料，研究了其气敏性能。结果表明，当在最佳工作温度220°C下暴露于75 ppm甲醇时，5 wt％La掺杂的SnO ₂纳米复合材料的感测响应达到29.5，这是纯SnO ₂纳米颗粒的七倍以上。此外，响应时间和恢复时间分别缩短到12 s和7 s。而且，在甲烷，甲醇，氨，丙酮和苯气体中，5重量％的La掺杂的SnO ₂纳米复合材料对甲醇具有良好的选择性。5 wt％的La掺杂SnO ₂的气敏特性的改善 朝向甲醇的纳米复合材料可归因于较小的微晶尺寸，较大的表面积以及纳米复合材料表面改性的化学性质。