rGO-MO_x复合纳米纤维的制备及其对VOCs敏感性能研究

发布时间：2018-06-17 04:01

本文选题：复合材料 + rGO-MOx　；参考：《郑州大学》2017年硕士论文

【摘要】：随着社会及工业生产的高速发展,产生的有毒、有害气体的种类及数量不断增加,气体传感器就是伴随着环境污染的日益严重而发展起来的。金属氧化物半导体气敏传感器具有生产成本低、体积小巧、气敏材料易制备等优点被广泛应用于气体检测,然而选择性差、工作温度高等缺点限制了其进一步发展。石墨烯因具有大比表面积、快的电子传输速度而被广泛用于传感器研究中。本课题主要研究将微量还原氧化石墨烯(rGO)与金属氧化物半导体材料如SnO_2、TiO_2复合提高氧化物半导体材料的气敏性能,采用静电纺丝技术制备氧化物半导体纳米纤维,并通过二步水热法在氧化物纳米纤维表面修饰rGO,以及在氧化物纳米纤维纺丝制备过程中,直接加入氧化石墨烯(GO),通过后续煅烧合成rGO/氧化物半导体复合纳米纤维气敏材料,系统研究rGO的加入及加入方式对rGO-氧化物半导体复合纳米纤维气敏性能的影响,具体研究内容如下:1.通过静电纺丝法制备TiO_2纳米纤维,通过在静电纺丝前驱液中加入rGO,调节静电纺丝参数制备出rGO/TiO_2复合纳米纤维,探讨了rGO的复合对于TiO_2纳米纤维形貌结构以及VOCs气敏性能的影响。结果显示,rGO的复合对于材料的形貌及晶体结构未产生巨大影响,并且提高了材料对VOCs的灵敏度。在250℃下,rGO/TiO_2复合材料对于200ppm乙醇气体的灵敏度达到43.24,是TiO_2灵敏度的22.8倍,其响应时间也较TiO_2纳米纤维有所减少。2.通过静电纺丝法制备纯TiO_2纳米纤维,然后通过二步水热法利用rGO对TiO_2纳米纤维进行表面修饰,制备出rGO表面修饰TiO_2纳米纤维。表征结果显示rGO使TiO_2表面形貌更加粗糙,但未影响TiO_2材料的晶体结构。气敏结果表明,rGO表面修饰的TiO_2纳米纤维进一步提升了材料的灵敏度,缩短了响应恢复时间。3.利用静电纺丝法制备rGO/SnO_2复合纳米纤维,二步水热法制备rGO表面修饰SnO_2纳米纤维,研究rGO对于其他n型金属氧化物半导体VOCs气敏性能的影响。气敏测试结果表明,rGO的复合以及表面修饰对于SnO_2纳米纤维灵敏度提升更加明显,在150℃下,rGO表面修饰SnO_2纳米纤维对100ppm乙醇的灵敏度高达287,并且与SnO_2纳米纤维相比,其响应与恢复时间均相对缩短。
[Abstract]:With the rapid development of social and industrial production, the types and quantities of toxic and harmful gases are increasing, and gas sensors are developing with the increasingly serious environmental pollution. The metal oxide semiconductor gas sensor has many advantages, such as low production cost, small volume and easy preparation of gas sensitive materials. The further development of gas detection, however, is limited by poor selectivity and high working temperature. Graphene has been widely used in sensor research for its large specific surface area and rapid electronic transmission speed. This topic is mainly to improve the micro reduction of graphene oxide (rGO) and gold oxide semiconductor materials such as SnO_2 and TiO_2. The gas sensing properties of oxide semiconductor materials are prepared by electrostatic spinning technology. The oxide semiconductor nanofibers are prepared by two step hydrothermal method, and rGO is modified on the surface of oxide nanofibers, and GO is directly added to the preparation of oxide nanofibers. The rGO/ oxide semiconductor is synthesized by subsequent calcination. The effect of addition and addition of rGO on the gas sensitive properties of rGO- oxide semiconductor composite nanofibers is systematically studied with nano fiber gas sensitive materials. The specific contents are as follows: 1. the TiO_2 nanofibers are prepared by electrostatic spinning, and the rGO/TiO_2 composite nanofibers are prepared by adding rGO in electrostatic spinning precursor and adjusting the parameters of electrostatic spinning. The effect of rGO composite on the morphology and VOCs gas sensing properties of TiO_2 nanofibers was investigated. The results showed that the composite of rGO had no great influence on the morphology and crystal structure of the material, and increased the sensitivity of the material to VOCs. At 250, the sensitivity of rGO/TiO_2 compound to 200ppm ethanol gas reached 4. 3.24, 22.8 times the sensitivity of TiO_2, and its response time is less than that of TiO_2 nanofibers..2. nanofibers are prepared by electrospinning. Then the surface modification of TiO_2 nanofibers by the two step hydrothermal method is used to prepare the rGO surface modified TiO_2 nanofiber. The result shows that rGO makes the surface of TiO_2 more surface morphologies. The crystal structure of TiO_2 materials is not affected, but the gas sensitivity results show that the TiO_2 nanofibers modified by rGO surface can further enhance the sensitivity of the materials and shorten the response time,.3. using the electrostatic spinning method to prepare rGO/SnO_2 composite nanofibers, and the two step hydrothermal method to prepare the rGO surface to modify the SnO_2 nanofibers, and to study rGO for other n. The gas sensitive performance of type metal oxide semiconductor VOCs. The gas sensitivity test results show that the sensitivity of rGO composite and surface modification is more obvious for SnO_2 nanofibers. At 150, the sensitivity of rGO surface modified SnO_2 nanofibers to 100ppm ethanol is higher than that of SnO_2 nanofibers, and the response and recovery time of the SnO_2 nanofibers are compared with the SnO_2 nanofibers. All of them are relatively short.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB33;TB383.1

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