摘要：当前环境污染日益严重，大气污染严重影响人们的生活质量，所以，敏感气体检测是进行保护环境的重要手段之一：还原性气体的检测有利于保障人们生命安全。SmFeO3是一种钙钛矿型复合金属氧化物，P型半导体。其纳米材料具有良好的气敏性能，具有广阔的研究和应用背景。

采用溶胶凝胶法制备SmFeO3纳米颗粒，利用X射线衍射仪和扫描电子显微镜表征SmFeO3的微结构和形貌。结果显示SmFeO3是单相的钙钛矿结构，平均晶粒尺寸约为40nm。利用气敏分析系统研究SmFeO3纳米颗粒的气敏性能，结果显示SmFeO3对乙醇气体极其敏感，其工作温度约为215℃，对200ppm乙醇灵敏度高达300，响应时间/恢复时间分别为15s和16s。SmFeO3优异的气敏参数表明该材料在酒敏探测中具有潜在的应用前景。

关键词：SmFeO3；溶胶凝胶；纳米材料；气敏

Abstract：The environmental pollution problem is becoming more and more serious, Air pollution severely affects people's quality of life.Therefore, Sensitive gas detection is one of the important means of protecting the environment: The detection of reducing gas is beneficial to the safety of people. SmFeO3 is a kind of Perovskite type composite metal oxide as well as p-type semiconductor. Its nano material has good properties of gas sensing, which has broad prospects for study and application.

SmFeO3 nanoparticles were synthesized by sol-gel method. X-ray diffractometer and scanning electron microscope were used to characterize SmFeO3.The  results show that, SmFeO3 is a single phase perovskite structure and the average grain size is about 40 nm. We study on gas sensitivity of SmFeO3 nanoparticles by gas sensing system. The results showes that SmFeO3 is very sensitive to ethanol. The working temperature is about 215℃. The sensitivity can reach 300 in 200ppm ethanol atmosphere. Response time / recovery time is 15s / 16s. The excellent gas sensitivity parameters of SmFeO3 indicate that the material has potential application prospect in alcohol detection.

Keywords: SmFeO3; sol-gel; nano material; gas sensing

目录

第一章绪论 1

1.1引言 1

1.2钙钛矿的晶体结构 2

1.3气敏传感器及气敏器件工作原理 3

1.4本文的研究内容 4

第二章纳米材料的制备及其表征方法 5

2.1纳米材料的制备方法 5

2.2气敏器件的制作 6

2.3常见的纳米材料表征方法 6

2.3.1X射线衍射（XRD） 6

2.3.2扫描式电子显微镜（SEM） 7

2.4材料的气敏性研究 8

第三章SmFeO3纳米颗粒的制备与气敏性研究 9

3.1SmFeO3纳米颗粒的制备 9

3.1.1实验所需要的药品及仪器 9

3.1.2样品的制备 9

3.2SmFeO3的纳米颗粒结构表征 10

3.2.1X射线衍射（XRD） 10

3.2.2扫描式电子显微镜（SEM） 11

3.3SmFeO3气敏材料的制备及气敏性研究 12

3.3.1气敏器件的主要参数 12

3.3.2气敏器件的制作及气敏测试