氧化铜复合材料的设计合成及NO_X气敏性研究

发布时间：2018-06-29 14:11

本文选题：CuO + CuO/ZnO复合材料　；参考：《黑龙江大学》2015年硕士论文

【摘要】：在各种各样的空气污染物中,NOx是一种有毒气体,大于1 ppm的NOx可以危害人体的呼吸系统以及肺组织。因此,在室温下制备高灵敏度以及具有快速响应时间的NOx的稳定传感器变得尤为重要。氧化铜和氧化锌是优秀的半导体材料,它们广泛地应用在气敏传感器领域。所以,本文通过一步简单的回流法可控合成了CuO材料以及CuO/ZnO复合材料,在室温的条件下对其进行NOx气敏测试,同时初步对气敏机理进行了探讨。首先,以硝酸铜(Cu(NO3)2·3H2O)为基底,PEO-PPO-PEO block copolymer(P123)为表面活性剂,氨水(NH3·H2O)作为沉淀剂的条件下,通过改变Cu(NO3)2·3H2O的浓度、回流时间以及回流温度,合成了由纳米片自组装的多级结构的CuO微球,并对其在室温下进行气敏测试。实验结果表明:CuO对97 ppm的NOx气体的灵敏度可达到64.36%,响应时间为8.67 s,检测限最低达到0.97ppm。增强的气敏性能是由于多级结构为目标气体提供更大的接触面积。其次,在制备纯CuO的回流条件下,加入Zn(NO3)2,合成出Cu O/ZnO复合材料(CZ),并在室温下进行NOx气敏性能的测试。实验中Zn(NO3)2·6H2O与Cu(NO3)2·3H2O质量为30%的时候合成的CZ-30的复合材料有最佳的性能。测试结果表明,CZ-30对97 ppm NOx灵敏度为91.22%,响应时间仅为4.0 s,检测限可达0.97 ppm。合成的CuO/ZnO复合材料表现出p型半导体特性。由于在复合材料中Zn的加入使得材料的导电性提高,EIS及Mott-Schottky测试表明,电荷更加容易转移,从而提高响应速度。因此,合成的CuO/ZnO复合材料比纯CuO表现出了更好的气敏性能。
[Abstract]:Among all kinds of air pollutants, no _ x is a toxic gas. No _ x > 1 ppm can harm human respiratory system and lung tissue. Therefore, it is very important to prepare a stable no _ x sensor with high sensitivity and fast response time at room temperature. Copper oxide and zinc oxide are excellent semiconductor materials, they are widely used in gas sensor field. Therefore, CuO materials and CuO / ZnO composites were synthesized by a simple reflux method in this paper. No _ x gas sensing test was carried out at room temperature, and the gas sensing mechanism was also discussed. Firstly, using copper nitrate (Cu (no _ 3) _ 2 3H _ 2O) as substrate PEO-PPO-PEO block copolymer (P123 as surfactant and ammonia water (NH _ 3H _ 2O) as precipitant, the multi-level structure CuO microspheres were synthesized by changing the concentration of Cu (no _ 3) _ 2 _ 3H _ 2O, reflux time and reflux temperature. The gas sensitivity was measured at room temperature. The experimental results show that the sensitivity of 1: CuO to no _ x gas of 97 ppm is 64.36, the response time is 8.67 s, and the detection limit is 0.97 ppm. Enhanced gas sensitivity is due to the multi-level structure providing larger contact area for the target gas. Secondly, CuO / ZnO composites (CZ) were synthesized by adding Zn (no _ 3) _ 2 under the reflux condition of pure CuO, and the no _ x gas sensing properties were measured at room temperature. When the mass ratio of Zn (no _ 3) _ 2 6H _ 2O and Cu (no _ 3) _ 23H _ 2O is 30%, the CZ-30 composite has the best properties. The results show that the sensitivity of CZ-30 to 97 ppm NOx is 91.22, the response time is only 4.0 s, and the detection limit is 0.97 ppm. The synthesized CuO / ZnO composites exhibit p-type semiconductor properties. Due to the addition of Zn in the composite, the conductivity of the composite is improved by EIS and Mott-Schottky test. It is shown that the charge transfer is easier and the response speed is improved. Therefore, the synthesized CuO / ZnO composites exhibit better gas sensitivity than pure CuO / ZnO composites.
【学位授予单位】：黑龙江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X831;TB33

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