Application of electrochemistry to single-molecule junctions: from construction to modulation

State-of-the-art molecular electronics focus on the measurement of electrical properties of materials at the single-molecule level. Experimentally, molecular electronics face two primary challenges. One challenge is the reliable construction of single-molecule junctions, and the second challenge is the arbitrary modulation of electron transport through these junctions. Over the past decades, electrochemistry has been widely adopted to meet these challenges, leading to a wealth of novel findings. This review starts from the application of electrochemical methods to the fabrication of nanogaps, which is an essential platform for the construction of single-molecule junctions. The utilization of electrochemistry for the modification of molecular junctions, including terminal groups and structural backbones, is introduced, and finally, recent progress in the electrochemical modulation of single-molecule electron transport is reviewed.