Strategy and Future Prospects to Develop Room-Temperature-Recoverable NO₂ Gas Sensor Based on Two-Dimensional...

Nitrogen dioxide (NO₂), a hazardous gas with acidic nature, is continuously being liberated in the atmosphere due to human activity. The NO₂ sensors based on traditional materials have limitations of high-temperature requirements, slow recovery, and performance degradation under harsh environmental conditions. These limitations of traditional materials are forcing the scientific community to discover future alternative NO₂ sensitive materials. Molybdenum disulfide (MoS₂) has emerged as a potential candidate for developing next-generation NO₂ gas sensors. MoS₂ has a large surface area for NO₂ molecules adsorption with controllable morphologies, facile integration with other materials and compatibility with internet of things (IoT) devices. The aim of this review is to provide a detailed overview of the fabrication of MoS₂ chemiresistance sensors in terms of devices (resistor and transistor), layer thickness, morphology control, defect tailoring, heterostructure, metal nanoparticle doping, and through light illumination. Moreover, the experimental and theoretical aspects used in designing MoS₂-based NO₂ sensors are also discussed extensively. Finally, the review concludes the challenges and future perspectives to further enhance the gas-sensing performance of MoS₂. Understanding and addressing these issues are expected to yield the development of highly reliable and industry standard chemiresistance NO₂ gas sensors for environmental monitoring.