Conductivity-Type Sensor Based on CNT-WO3 Composite for NO 2 Detection. (19th March 2008)

• Record Type: Journal Article
• Authors: Hashishin, Takeshi; Tamaki, Jun
• Other Names: Wang Y. Academic Editor.
• Is Part Of: Journal of nanomaterials. Volume 2008(2008)
• Publication Date: 2008-03-19
• Subjects: Nanostructured materials -- Periodicals; Nanotechnology -- Periodicals; Nanomatériaux; Nanostructured materials; Nanotechnology; Nanostructures; Nanotechnology; Periodicals; Fulltext; Internet Resources; Periodicals; 620.115
• DOI: 10.1155/2008/352854
• Languages: English
• ISSNs: 1687-4110

Abstract

Abstract : The CNTs with 20–50 nm in diameter were directly grown on Au microgap electrode by means of thermal CVD at700 ∘ C for 60 minutes under EtOH-Ar-H 2 atmosphere (6 kPa). The CNTs with entangled shape formed the network structure with contacting each other. In the CNTs-WO 3 composite, WO 3 grains with disk shape (50–200 nm) were independently trapped. The CNTs-WO 3 composite sensor showed the fairly good sensor response (Ra/Rg = 3.8 at200 ∘ C). The sensor response was greatly improved with CNTs-WO 3 composite, comparing with that of CNT sensor (Ra/Rg = 1.05). This phenomenon can be explained by formation of p-n junction, between CNT(p) andWO 3 (n), and thus improvement ofNO 2 adsorption. The sensor response was decreased with increasing theWO 3 amount in CNTs-WO 3 composite, suggesting the electronic conduction due toWO 3 connection.