摘要
本工作利用静电纺丝和浸渍法合成了Co3O4复合的SnO2纳米纤维，系统地表征了材料的成分和形貌，研究了其气敏性能．结果表明，Co3O4的修饰显著提升了SnO2纳米纤维对乙醇气体的响应特性．相比于未修饰的SnO2纳米纤维，复合量为12mol％的Co3O4／SnO2纳米纤维在300℃下对100ppm乙醇气体的响应提高了57倍，达到了38．0，而且，响应和恢复时间也火幅降低．该样品对乙醇气体的选择性优异，其响应值随乙醇浓度呈幂指数变化．Co3O4修饰提升SnO2气敏性能的原因可能与形成的p—n异质结有关.
SnO2 nanofibers were synthesized by electrospinning and modified with Co3O4 via impregnation in this work. Chemical composition and morphology of the nanofibers were system- atically characterized, and their gas sensing properties were investigated. Results showed that Co3O4 modification significantly enhanced the sensing performance of SnO2 nanofibers to ethanol gas. For a sample with 1.2 mol% Co3O4, the response to 100 ppm ethanol was 38.0 at 300 ℃, about 6.7 times larger than that of SnO2 nanofibers. In addition, the response/recovery time was also greatly reduced. A power-law dependence of the sensor response on the ethanol concentration as well as excellent ethanol selectivity was observed for the Co3O4/SnO2 sensor. The enhanced ethanol sensing performance may be attributed to the formation of p-n heterojunctions between the two oxides.
基金
This work was supported by the National Natural Science Foundation of China （No.U1432108） and the Fundamental Research Funds for the Central Universities （No.WK2320000034）.
