發(fā)布時間：2018-02-28 02:14

  本文關鍵詞： 氣體傳感器 復合材料 ZnO納米纖維 還原氧化石墨烯 氣敏性能　出處：《鄭州大學》2017年碩士論文　論文類型：學位論文

【摘要】：氣體傳感器作為檢測氣體成分及濃度的重要工具在眾多領域扮演著十分重要的角色,金屬氧化物半導體傳感器因價格低廉、靈敏度高、響應速度快等優(yōu)點而受到了眾多科研工作者的青睞,其中擁有寬禁帶寬度、大激子束縛能的ZnO納米材料是一種優(yōu)良的氣敏材料,被廣泛應用于氣體傳感器的研究中。然而,單一的ZnO氣敏材料工作溫度高、選擇性差的問題仍然需要改進。自新型碳單質石墨烯被發(fā)現后,因其優(yōu)良的性能和潛在的應用前景受到了廣泛的關注。本文將以ZnO納米纖維為基礎材料,通過與微量石墨烯復合以及金屬摻雜來提高氣敏性能,具體研究工作如下:1.利用靜電紡絲法制備ZnO納米纖維,rGO(還原氧化石墨烯)與ZnO的復合通過兩種方法進行制備,一是將煅燒后的ZnO納米纖維與rGO溶液通過水熱法制備,二是ZnO紡絲前驅體溶液中,直接加入適量的rGO,經紡絲煅燒后直接獲得rGO/ZnO復合納米纖維。研究表明,通過二步水熱法及靜電紡絲法獲得的rGO-ZnO復合納米纖維對H2S的氣敏性能均有明顯的提高。在200℃的工作溫度下,rGO修飾ZnO納米纖維對1ppmH2S氣體的靈敏度可達6.8,是ZnO納米纖維的2.7倍,而rGO/ZnO復合納米纖維對1ppmH2S氣體的靈敏度可達到20.6,是ZnO納米纖維的8.2倍。且在同一溫度下兩種復合材料對其他干擾氣體的靈敏度沒有明顯提高,說明通過二步水熱法和直接紡絲獲得的復合氣敏材料其選擇性均有明顯提高。2.研究了rGO與Cu摻雜ZnO復合納米纖維的氣敏性能。采用二步水熱法和靜電紡絲直接復合兩種方式分別制備了rGO修飾Cu摻雜ZnO納米纖維和rGO/Cu摻雜ZnO復合納米纖維,測試了材料的氣敏性能。結果表明,rGO修飾Cu摻雜ZnO納米纖維在200℃下,對1ppm H2S氣體靈敏度可達到43。而rGO/Cu摻雜ZnO復合納米纖維在工作溫度為100℃時對1ppm的H2S的靈敏度可高達169,比Cu摻雜ZnO納米纖維的靈敏度提高了57倍,比ZnO納米纖維的靈敏度提高了66倍,并且r GO/Cu摻雜ZnO復合氣敏材料的最佳工作溫度相比ZnO納米纖維及rGO修飾Cu摻雜ZnO納米纖維均明顯降低,說明通過靜電紡絲復合rGO的方法更大程度的優(yōu)化了氣敏性能。3.研究了rGO與In摻雜ZnO復合納米纖維的氣敏性能。采用二步水熱法和靜電紡絲直接復合兩種方式分別制備了rGO修飾In摻雜ZnO納米纖維和rGO/In摻雜ZnO復合納米纖維。通過SEM表面形貌測試發(fā)現,In的摻雜改變了ZnO納米纖維的表面形貌,在Zn O納米纖維表面均勻分布著直徑極小的In2O3納米棒。氣敏特性測試表明,通過靜電紡絲法制備出的rGO/In摻雜ZnO納米纖維在200℃時,對10ppm的NO氣體靈敏度為30。通過水熱法制備出的rGO修飾In摻雜ZnO納米纖維的最佳工作溫度為150℃,比In摻雜ZnO納米纖維的最佳工作溫度降低了50℃,在此溫度下對10ppm的NO氣體靈敏度為36,是ZnO納米纖維靈敏度的30倍。
[Abstract]:As an important tool for detecting gas composition and concentration, gas sensors play a very important role in many fields. Metal oxide semiconductor sensors have low price and high sensitivity. ZnO nanomaterials with wide band gap and high exciton binding energy are one of the excellent gas sensing materials, which have been widely used in the research of gas sensors, however, because of their fast response speed and so on, the ZnO nanomaterials with wide band gap and high exciton binding energy are widely used in the research of gas sensors. The problems of high temperature and poor selectivity of single ZnO gas sensing materials still need to be improved. Because of its excellent properties and potential application prospects, ZnO nanofibers will be used as the basic materials to improve the gas sensitivity by combining with trace graphene and doping metal. The specific research work is as follows: 1. The composite of ZnO nanofibers rGOand ZnO was prepared by electrospinning method. The first method was to prepare the calcined ZnO nanofibers with rGO solution by hydrothermal method. Secondly, the ZnO composite nanofibers were obtained by adding appropriate amount of rGOinto the solution of ZnO spinning precursor directly after spinning and calcining. The gas-sensing properties of rGO-ZnO nanofibers obtained by two-step hydrothermal method and electrostatic spinning method were improved obviously. The sensitivity of ZnO nanofibers modified by ZnO at 200 鈩，

本文編號：1545315