Heterostructures of 2D materials and their applications in biosensing

• Synthesis, characterization, and properties of the 2D heterostructures are summarized. • The working principles, types, and techniques used for biosensor fabrications are studied. • Different 2D heterostructured and their performance in biosensors are reviewed. • Current challenges and future perspectives of the 2D heterostructures are highlighted. Heterostructures of two-dimensional (2D) materials have attracted attention due to their structures and multifunctional interfacial characteristics. The unique properties of these heterostructures are primarily due to electronic structure modification (Fermi energy level, the density of states, synergetic work function, and so on) at the interface. The high transparency, atomic thickness, vast specific area, exceptional optical/electrical properties, and additional biocompatibility of 2D heterostructure materials and their application as various biosensors, including electrochemical, surface plasma resonance, immunosensor, photoelectrochemical, nucleic acid-based, enzyme-based, aptamer, protein-based, and electrochemiluminescent biosensors. Finally, the synthesis strategies, physicochemical properties, fabrication, working mechanism, and performances of these 2D heterostructured material-based biosensors are discussed. The current challenges and future perspectives of this study are highlighted. This review will encourage innovative visions and technical advances for upcoming research.