Rapid and Efficient NO(2) Sensing Performance of TeO(2) Nanowires

Gas sensors play a pivotal role in environmental monitoring, with NO(2) sensors standing out due to their exceptional selectivity and sensitivity. Yet, a prevalent challenge remains: the prolonged recovery time of many sensors, often spanning hundreds of seconds, compromises efficiency and undermines the precision of continuous detection. This paper introduces an efficient NO(2) sensor using TeO(2) nanowires, offering significantly reduced recovery times. The TeO(2) nanowires, prepared through a straightforward thermal oxidation process, exhibit a unique yet smooth surface. The structural characterizations confirm the formation of pure-phase TeO(2) after the anneal oxidation. TeO(2) nanowires are extremely sensitive to NO(2) gas, and the maximum response (defined as the ratio of resistance in the air to that under the target gas) to NO(2) (10 ppm) is 1.559. In addition, TeO(2) nanowire-based sensors can return to the initial state in about 6–7 s at 100 °C. The high sensitivity can be attributed to the length–diameter rate, which adsorbs more NO(2) to facilitate the electron transfer. The fast recovery is due to the smooth surface without pores on TeO(2) nanowires, which may release NO(2) quickly after stopping the gas supply. The present approach for sensing TeO(2) nanowires can be extended to other sensor systems as an efficient, accurate, and low-priced tactic to enhance sensor performance.