ZnO‐SnO₂ composite nanofibers with a constant Zn/Sn ratio of 0.4 have been electrospun and calcined at 650°C in ambient air, followed then by heat treatment at 350°C in either air, 5% H₂‐95% N₂, or 15 ppm H₂S‐air atmosphere for comparison of gas‐sensing behaviors. The nanofibers being heat‐treated in the H₂S‐air atmosphere display a sensing response more than 25 times than the as‐calcined counterpart, that is, the sensing response increases from 20 to 514 against a model NO₂ gas of 10 ppm concentration at a working temperature of 180°C. This appears to be attributable to the formation of sulfate on the nanofiber surface, which resulted in an enriched oxygen vacancy and chemisorbed oxygen near the surface for facilitating the redox reaction toward NO₂ gas molecules. The facile heat treatment in the presence of dilute H₂S concentration may have opened up an alternative route for enhancing the surface‐sensitive gas‐sensor activity.

中文翻译：

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热处理对电纺ZnO-SnO2复合纳米纤维表面结构和气敏性的影响

Zn / Sn恒定比为0.4的ZnO-SnO ₂复合纳米纤维已经电纺并在650°C的环境空气中煅烧，然后在350°C的任何一种空气中进行5％H ₂ -95％N _2的热处理或15 ppm H ₂ S空气气氛，用于比较气体传感行为。在H ₂ S空气中进行热处理的纳米纤维的传感响应是煅烧纳米纤维的25倍以上，也就是说，对于NO _2型，传感响应从20增加到514。在180°C的工作温度下浓度为10 ppm的气体。这似乎归因于在纳米纤维表面上形成硫酸盐，其导致表面附近富集的氧空位和化学吸附的氧，从而促进了向NO ₂气体分子的氧化还原反应。在稀的H ₂ S浓度下进行简便的热处理可能为提高表面敏感型气体传感器的活性开辟了另一条途径。