Ammonia Gas Sensing Properties of Nanocrystalline Zn^sub 1-x^Cu^sub x^Fe^sub 2^O^sub 4^ Doped with Noble Metal

• Published in: Sensors & transducers Vol. 122; no. 11; p. 120
• Main Authors: Jagtap, S V, Kadu, A V, Gedam, N N, Chaudhari, G N
• Format: Journal Article
• Language: English
• Published: Toronto IFSA Publishing, S.L 01.11.2010
• Subjects: Ammonia; Atoms & subatomic particles; Environmental monitoring; Gases; Polyvinyl alcohol; Pressure vessels; Scanning electron microscopy; Sensors
• ISSN: 2306-8515; 1726-5479

The sensors are required basically for monitoring of trace gases in environment. In order to detect, measure and control these gases; one should know the amount and type of gases present in the environment. Among the most toxic and hazardous gases, it is necessary to detect and monitor the ammonia gas because this is enhance in the agricultural sector by the addition of large amounts of NH^sub 3^ to cultivated farmland in the form of fertilizers. Nanocrystalline spinel type Zn^sub 1-x^Cu^sub x^Fe^sub 2^O^sub 4^ (x=0, 0.2, 0.4 0.6 & 0.8) has been synthesized by sol-gel citrate method. The synthesized powders were characterized by XRD and SEM. The results revealed that the particle size is in the range of 40-45 nm for Cu-Zn ferrite with good crystallinity. The gas sensing properties were studied towards reducing gases like CO, LPG, NH^sub 3^ and H^sub 2^S and it is observed that Cu-Zn ferrite shows high response to ammonia gas at relatively lower operating temperature. The Zn^sub 0.6^Cu^sub 0.4^Fe^sub 2^O^sub 4^ nanomaterial shows better sensitivity towards NH^sub 3^ gas at an operating temperature 300 °C. Incorporation of Pd improved the sensitivity, selectivity, response time and reduced the operating temperature from 300 °C to 250 °C for NH^sub 3^ sensor. [PUBLICATION ABSTRACT]