Metal-organic framework-derived In2O3@MoS2 nanocomposites: Enabling highly sensitive NO2 sensing with robust humidity tolerance at near-room temperature

In complex practical environments, gas sensors with exceptional anti-interference capabilities are highly desirable. Nevertheless, developing metal oxide-based NO₂ gas sensors that maintain excellent humidity resistance at relatively low temperatures remains a significant challenge. In this work, Metal-organic framework-derived In₂O₃@MoS₂ heterojunctions were successfully fabricated, which demonstrate remarkable NO₂ sensing performance characterized by low operating temperature, high selectivity, and outstanding humidity tolerance. Significantly, at near room temperature, the sensor demonstrates negligible response fluctuation of only 1.03 % to 10 ppm NO₂ across a wide relative humidity (RH) range of 15 %-85 %. Even at 65 % RH conditions, it still achieves a low detection limitation of 50 ppb. Further analysis reveals that edge-terminated unsaturated sulfur (S) atoms are the key factor for the enhanced sensing performance. Both porous strueture and enhanced charge transfer are also conducive to the enhancement. These findings highlight the potential of In₂O₃@MoS₂-based gas sensor as promising candidates for reliable NO₂ detection in high-humidity environments.