Current Science Research Bulletin

Recent advances in nanotechnology, artificial intelligence (AI), the Internet of Things (IoT), and smart electronics have significantly increasedthe demand for high-performance sensorswith high sensitivity, fast response, low power consumption, and miniaturized dimensions. This review presents an overview of recent research progress on novel materials for sensing applications, focusing on their structural characteristics, sensing mechanisms, and potential applications in gas sensors, biosensors, optical sensors, and wearable electronics. Various advanced nanomaterials, including Graphene, Carbon Nanotubes, Silicene, Germanene, Stanene, Transition Metal Dichalcogenides, MXenes, metal-oxide nanomaterials, Perovskite materials, conducting polymers, and plasmonic nanostructures are discussed in detail. These materials exhibit remarkable sensing performance because of their large specific surface area, tunable electronic properties, strong adsorption capability, and excellent charge-transfer efficiency. In particular, low-dimensional materials have demonstrated outstanding sensitivity toward toxic gases, biomolecules, and optical signals, even at room temperature. The review also highlights the important role of Density Functional Theory (DFT) in predicting adsorption mechanisms, electronic structures, and sensing behaviorbefore experimental fabrication. In addition, emerging trends such as nano-heterostructures, flexibleand wearable sensors,self-powered devices, and AI- integrated sensing systems are summarized. Furthermore, recent developments in hybrid nanocomposites and multifunctional sensing platforms have opened new opportunities for next- generation healthcare monitoring, environmental protection, industrial safety, and smart-city technologies. The integration of machine learning techniques with sensor systems has also improved signal processing, real-time detection, and data analysis accuracy. Finally, current challenges and future perspectives toward sustainable, intelligent, low-cost, and high-performance sensor technologies are discussed, emphasizing the importance of interdisciplinary research in advancing practical sensing applications for future electronic and biomedical systems.

MXenes; gas sensors; biosensors; smart sensors.

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