Heterostructured Semiconductors for Advanced Chemical and Biochemical Sensors: From Gas Sensors to Electrolyte‐Gated Transistors

ABSTRACT

Heterostructured semiconductors have attracted significant attention in chemical and biochemical sensing due to their ability to combine complementary electronic, catalytic, and interfacial properties within a single sensing platform. The integration of semiconducting metal oxides (SMOs), organic semiconductors (OSCs), transition metal dichalcogenides (TMDs), metallic nanoparticles (MNP), and carbon‐based materials enable enhanced charge transport, analyte adsorption, and signal transduction, resulting in improved sensitivity, selectivity, and stability. In parallel, different transduction mechanisms, including electronic, electrochemical, and iontronic approaches, have expanded the applicability of semiconductor‐based sensors toward environmental, industrial, and biomedical monitoring. This review presents a comparative discussion of heterostructured semiconductor materials employed in sensing devices operating through distinct transduction mechanisms, with emphasis on gas sensors and electrolyte‐gated transistor (EGT)‐based platforms. Fundamental aspects of sensing architecture and device operation are initially introduced, followed by a systematic overview of SMO‐ and OSC‐based heterostructures combined with TMDs, metallic nanoparticles, carbon nanomaterials, and polymeric systems. The relationships between heterointerface engineering, charge‐transfer mechanisms, and sensing performance are critically discussed. Finally, current challenges, emerging trends, and future perspectives associated with multifunctional heterostructured sensing platforms are addressed, highlighting their potential for next‐generation wearable, portable, and intelligent sensing technologies.