Advancements in 2D TMDs as Sensors: From Materials to Real-World Applications

This review provides a comprehensive analysis of the performance of transition-metal dichalcogenides (TMDs) and their hybrid nanostructures in various sensing applications, including gas sensors, photodetectors, biosensors and wearable sensors. It focuses on categorizing the mechanisms involved, such as chemiresistive, field-effect transistor (FET), surface-enhanced Raman scattering (SERS) and piezoresistive methods, which illustrate the sensor functionalities of TMDs. The review emphasizes the importance of several properties like charge transfer processes, surface interactions and structural dynamics. The interaction between TMDs and target molecules leads to necessary modifications that influence the sensor's output signal, including defect formation, doping effects and bandgap adjustments (ranging from 1 to 2 eV). Additionally, the review investigates other critical parameters that enhance sensor performance, like the number of TMD layers, functionalization methods and various chemical and physical environments. These factors can significantly improve selectivity by up to 200% and decrease response times to just a few milliseconds. To further enhance the sensitivity, selectivity and stability of TMD-based sensors, reproducibility and other relevant parameters are also discussed in light of recent advancements. The key findings presented here provide valuable insights for researchers aiming to leverage TMDs in the development of next-generation sensor technologies, with a focus on optimizing sensitivity and selectivity.