Conducting polymer and metal-based sensors for the detection of vapours and toxic gases: A concise review

Abstract

Monitoring the concentration of gases and volatile compounds in the environment has significant impact on sustainable human development due to global industrialization. Gas sensors are being employed since 1970’s for detecting noxious gases, gas leakages, and also for observing humidity and atmospheric composition. The approach of designing miniature and portable gas/vapour sensors exhibiting rapid response and reversibility together with selectivity and sensitivity has been highly demanding.  Similarly, development in the area of nano-technology has encouraged the scientists to fabricate nano sensors. Sensor devices have been made from classical semiconductors, solid electrolytes, insulators, metals etc. However, the development of conducting polymer-based sensors has unfolded a new dimension in sensing by enabling the wide scope toward the detection of chemical/water vapours and toxic gases even in complex environment. Whereas, the metal oxide-based sensors were observed to be efficient toward the detection of toxic gases. The present review provides a concise account of our work on conducting polymers and metal-based sensors for ammonia, alcohol, chloroform, humidity, toxic gases etc. Additionally, the paper also demonstrates the challenges and future prospects of conducting polymer sensors to pave their way for enhancing their sensing efficacy.