A Rapid Room-Temperature NO₂ Sensor Based on Tellurium–SWNT Hybrid Nanostructures

Abstract

One-dimensional nanostructure-based chemiresistive sensors have received great attention because of their compact design and excellent sensing performance, including high sensitivity, low detection limits, low power consumption, and the ability to integrate multisensor arrays. However, these sensors generally suffer from slow response and recovery times when they are operated at ambient conditions because of slow catalytic or absorption/desorption processes. The sensors overcome this obstacle by operating at high temperature, which increases the device complexity with a higher power consumption rate. In this work, we demonstrated the construction of an ultrafast NO2 sensor at ambient conditions by utilizing feather-like tellurium (Te) nanostructures functionalized on single-walled carbon nanotube networks. By tailoring the morphology and density of Te nanostructures, hybrid nanostructures show excellent response and recovery times of approximately 63 s and 7 min to 100 ppbV NO2 gas at room temperature.