为开发室温NO气敏传感器,采用SnCl2溶液法合成了MWCNTs/SnO2复合材料,并对复合材料进行了XRD,Raman,SEM,TEM,TG - DSC及XPS表征.结果表明:在MWCNTs/SnO2复合材料中,尺寸为5 nm左右的SnO2颗粒均匀地负载在MWCNTs表面,MWCNTs与SnO2的质量之比基本恒为3∶1,不随所加羧基化MWCNTs量的不同(30～100 mg)而变化.利用静态注气法考察的MWCNTs/SnO2复合材料室温NO气敏响应特性表明,MWCNTs/SnO2复合材料对NO的气敏响应有了较大的提高,对100 × 10-6 NO的响应值大约是MWCNTs的4倍.将纳米SnO2负载在MWCNTs的表面之所以能够明显提高MWCNTs的室温NO响应值,是由于复合材料吸附NO分子时电子由p型半导体MWCNTs向SnO2转移的结果.%In order to develop NO gas sensor working at room temperature, Multi - Walled Carbon Nanotubes ( MWCNTs) and SnO2 composite was synthesized by SnCl2 solution method, and the composite was characterized by XRD, Raman, SEM, TEM, TG - DSC and XPS methods. It was observed that SnO2 nanoparticles of only 5 nm were deposited uniformly on the surface of MWCNTs in the MWCNTs/SnO2 composite. The weight ratio of MWCNTs to SnO2 in the composite was kept 3:1 though different amount of carboxylated MWCNTs (30 ~ 100 mg) was used in the synthesis process. The NO response property of MWCNTs/SnO2 composite was investigated at room temperature by static testing. It was shown that the MWCNTs/SnO2 sensor's response has increased by a factor of four in comparison with that of MWCNTs toward 100 x 10-6 NO. Therefore, modification of SnO2 nanoparticles on the surface of MWCNTs could improve significantly the response of MWCNTs toward NO at room temperature. This was because the electrons transferred from p - type MWCNTs to SnO2 when NO molecules were adsorbed on the MWC-NTs/SnO2 composite.
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