物理化学学报 >> 2015, Vol. 31 >> Issue (10): 1997-2004.doi: 10.3866/PKU.WHXB201508241

材料物理化学 上一篇    下一篇

PdO, Au, CdO修饰SnO2纳米纤维的制备及其气敏特性

胡瑞金,王兢*(),朱慧超   

  • 收稿日期:2015-05-25 发布日期:2015-10-10
  • 通讯作者: 王兢 E-mail:wangjing@dlut.edu.cn
  • 基金资助:
    国家自然科学基金(61176068, 61131004, 61107028)

Preparation and Gas Sensing Properties of PdO, Au, CdO Coatings on SnO2 Nanofibers

Rui-Jin. HU,Jing. WANG*(),Hui-Chao. ZHU   

  • Received:2015-05-25 Published:2015-10-10
  • Contact: Jing. WANG E-mail:wangjing@dlut.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(61176068, 61131004, 61107028)

摘要:

采用静电纺丝的方法制备了SnO2纳米纤维,并分别用PdO、Au、CdO对该纳米纤维材料进行表面修饰.用X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线能谱(EDX)、X射线光电子能谱(XPS)分析、Brunauer-Emmett-Teller (BET)比表面积测试对材料进行表征.修饰前后, SnO2纳米纤维都是由约15 nm的纳米颗粒构成的直径约为200 nm的多级结构材料.采用静态测试系统对纯SnO2及不同物质修饰的SnO2的气敏特性进行测试,结果表明,未修饰的SnO2纳米纤维气敏元件对甲醛具有较好的响应.修饰后的SnO2材料的气敏特性都有明显的改善. CdO修饰的SnO2气敏元件对甲醛的响应值最高,且响应恢复时间短,选择性好. Au修饰的SnO2气敏元件对甲醛响应的最佳工作温度从300 ℃降到了200 ℃.经PdO修饰后, SnO2纳米纤维对甲苯的响应值变得最高.初步分析了经过修饰的SnO2气敏材料的敏感机理.

关键词: 气体传感器, SnO2, 修饰, 静电纺丝, 气敏机理

Abstract:

SnO2 nanofibers fabricated by electrospinning were coated with PdO, Au, and CdO. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET) tests were used to characterize the nanofibers. The diameters of bare and coated SnO2 nanofibers were approximately 200 nm, and had 15-nm diameter grains. The gas-sensing properties of all the nanofibers were characterized under static gas conditions. The results indicated that the bare SnO2 nanofibers were sensitive to formaldehyde; however the sensitivity of the coated nanofibers was better. In particular, the CdO-coated SnO2 exhibited the highest sensitivity to formaldehyde, the shortest response and recovery times, and good selectivity. The operating temperature of the Au-coated SnO2 decreased from 300 to 200 ℃, while the PdO-coated SnO2 exhibited the highest sensitivity to toluene. The sensing mechanism of the coated SnO2 nanofibers was investigated.

Key words: Gas sensor, SnO2, Coating, Electrospinning, Gas sensing mechanism