Interface Engineering in Sensor Devices

The metal oxide nanoparticle based resistive gas sensors are becoming increasingly common due to their affordability, small size, and ease of integration with analog interface circuits. Due to their low detection limit (ppb to ppm) and high sensitivity to gases, semiconducting metal oxides are most frequently utilized as the sensing layer in gas sensors. However, because they typically react to both oxidizing and reducing gas molecules, metal oxides have poor selectivity. They may also experience baseline drift and stability issues, as well as degradation in certain situations when exposed to humidity. The use of interfacial engineering in sensor devices, such as the formation of heterojunctions, noble metal loading (e.g., Au, Pt, Ag, Pd), and nano structural modification via incorporation of 2D materials or MOF’s in the interfaces can help to mitigate some of these shortcomings. The review investigates the mechanisms underlying their improved response at room temperature, including the use of heterojunctions to enhance the response, metal particle sensitization to improve gas adsorption, and special structures to enhance the effective area of surface in the sensors. Finally, we explore the new uses for interface-engineered gas sensors, which offer a practical way to improve interface stability and performance, especially in environmental safety and food quality management.