ABSTRACT
Quantum dots (QDs) are colloidal nanoparticles consisting of a semiconductor material and are defined by the occurrence of quantum confinement. The photoelectrochemical (PEC) technique combines the advantages of electrochemical methods that include low cost, simple instrumentations, high sensitivity, and portability, with the light-triggered read-out without the necessity of expensive optical equipment. PEC QD-based systems rely on sequential charge transfer processes inside the nanoparticles, between the electrode and the QDs and between the QDs and the analyte in solution. The recombination of photoexcited charge carriers inside the QDs limits the performance of photoelectrochemical systems. Surface trap states are energetic states, mostly in the bandgap of the semiconductor and can usually be found at the particle surface. The interest in using of QD electrodes for photoelectrochemical analysis and bioanalysis has led to different sensor formats for the sensitive and specific detection of a number of important analytes.
