Frontiers in Single-Molecule Junction Detection: A Review of Recent Innovations and Breakthroughs

Single-molecule junction techniques offer powerful tools for studying physical and chemical properties at the single-molecule level, while enabling groundbreaking advances in ultrasensitive sensing. This review encapsulates the latest progress made in tracking chemical reactions and intermolecular interactions by employing single-molecule junction techniques. Additionally, we explore their practical applications in detection and sensing of trace chemical substances and biomolecules. Single-molecule electrical measurements, such as mechanically controllable break junctions (MCBJs), scanning tunneling microscopy break junctions (STM-BJs), and graphene-molecule-graphene single-molecule junctions (GMG-SMJ), exhibit exceptional sensitivity and resolution. These techniques allow for precise control and detection at the molecular scale, providing powerful tools for research across disciplines such as chemistry, biology, and physics while also driving new discoveries and advancements in related fields. Furthermore, we highlight the applications of single-molecule junction-based sensing techniques in identifying small molecules and ions in various media, thus contributing noteworthy insights into the design of ultrasensitive single-molecule sensors.