Recent progress in carbon nanotube-based gas sensors

TLDR

Carbon‑nanotube gas sensors, especially chemiresistors and field‑effect transistors, have attracted intense research because their nanostructured electrical properties change rapidly and selectively when exposed to gases, enabling miniature, low‑power detection. This review summarizes recent advances in the development of various CNT‑based nanosensors. Researchers enhance sensitivity, selectivity, and response time by rationally functionalizing CNTs covalently or non‑covalently with polymers, metals, and other materials.

Abstract

The development of carbon nanotube-(CNTs-)based gas sensors and sensor arrays has attracted intensive research interest in the last several years because of their potential for the selective and rapid detection of various gaseous species by novel nanostructures integrated in miniature and low-power consuming electronics. Chemiresistors and chemical field effect transistors are probably the most promising types of gas nanosensors. In these sensors, the electrical properties of nanostructures are dramatically changed when exposed to the target gas analytes. In this review, recent progress on the development of different types of CNT-based nanosensors is summarized. The focus was placed on the means used by various researchers to improve the sensing performance (sensitivity, selectivity and response time) through the rational functionalization of CNTs with different methods (covalent and non-covalent) and with different materials (polymers and metals).