掺锡对α-Fe_2O_3薄膜微结构和气敏特性的影响研究

Effects of Sn doping on the Microstructure and Gas Sensing Properties of α Fe 2O 3

本文用常压化学气相淀积法（ＡＰＣＶＤ）制备了α－Ｆｅ２Ｏ３薄膜，对所制备的薄膜进行了Ｘ射线衍射分析和表面形貌（ＳＥＭ）分析。对薄膜的气敏特性进行了测量。结果表明，用ＡＰＣＶＤ工艺制备的α－Ｆｅ２Ｏ３薄膜对烟雾极为敏感并且具有良好的选择性；本研究还对所制备的α－Ｆｅ２Ｏ３薄膜进行了有效的掺杂，对掺杂样品的气敏特性测试表明四价金属元素Ｓｎ的掺入对α－Ｆｅ２Ｏ３薄膜的气敏特性有显著的影响。实验表明用ＡＰＣＶＤ法制备掺Ｓｎ４＋的α－Ｆｅ２Ｏ３薄膜不仅大幅度提高了材料对烟雾的灵敏度，同时也使得选择性得到明显改善。

Haematite(α Fe 2O 3) thin films are prepared by atmospheric pressure chemical vapour deposition(APCVD).The films are characterized by X ray diffraction and scanning electron microscopy (SEM). Their gas sensing properties are also investigated. Experimental results show that APCVD α Fe 2O 3 films are highly sensitive to smoke and the selectivity is good. A quadrivalent metal Sn has been incorporated to APCVD α Fe 2O 3 thin films effectively. Experiments show that Sn has an effect on α Fe 2O 3 gas sensing properties. It is found that Sn doping α Fe 2O 3 thin films made by APCVD exhibit a higher sensitivity to smoke than pure α Fe 2O 3 thin films and selectivity is improved obviously.