Quantum dots-based photoelectrochemical sensors and biosensors

Abstract Photoelectrochemistry has been one of the most frequently studied branches of chemistry for the past 2 decades and its principle is based on monitoring a photocurrent generated by the irradiation of photosensitive material on an electrode surface with a light source. Photoelectrochemical (PEC) analysis has found wide applications in various fields such as water splitting, hydrogen or oxygen production, pollutant degradation, CO2 reduction, and construction of sensors and biosensors. In PEC studies, various photosensitive materials such as organic redox mediators (ORMs), semiconductors, heterostructures, and composite nanomaterials have been used. Among these, quantum dots (QDs) are of great interest to researchers because of their unique and superior optical and electronic properties. In this chapter the principles and mechanisms of PEC-sensing strategies using ORMs, QDs or their hybrid nanostructures are described and applications of PEC-sensing platforms such as in small analyte detection, immunoassays, nucleic acids, and enzyme-based biosensors.