Enhancement of gas sensor response characteristics of functionalized SWCNTs

• Main Authors: Ansari, Nagma, Lone, Mohd Yaseen, Ali, Javid, Husain, Mushahid, Husain, Samina
• Format: Conference Proceeding
• Language: English
• Subjects: Ammonia; Chemisorption; Gas sensors; Nitric acid; Raman spectroscopy; Recovery; Response time; Room temperature; Sensors
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0026156

This paper reports and compares NH3 gas sensor response of the HNO3 functionalized SWCNTs (f-SWCNTs) and pristine-SWCNTs (p-SWCNTs). The role of (pristine and functionalized) SWCNTs for detecting NH3 gas is evaluated in terms of the sensors response, response time and sensor recovery. The results show that SWCNTs are successfully functionalized using 3M nitric acid which is confirmed through FTIR analysis. The as-synthesized samples are characterized using techniques like FESEM and Raman Spectroscopy. The study has been performed on the exposure of NH3 (8 ppm) at room temperature (40°C). The observed sensor response of p-SWCNTs and f-SWCNT sensors were 2.9% and 5.8% respectively. f-SWCNTs sensor reports an enhanced sensor response with fast response time (3 mins.), however its recovery remained slow (7 mins.) as compared to p- SWCNTs sensor respectively. The reason may be attributed to the interaction of NH3 with p-SWCNTs surface which is predominantly physisorption, whereas in f- SWCNTs it is mainly governed by the complex chemisorption process. The obtained results are in good agreement with previous reported work with enhanced NH3 gas sensor response characteristics.