Bridging materials and interfaces: Interfacial engineering of charge dynamics in photodetectors

The rapid progress in photodetector technologies has significantly driven the advancement of optoelectronics applications, ranging from high-speed optical communication and biomedical engineering to wearable electronics and autonomous systems. Consequently, these developments impose several key performance parameters, including a minute amount of dark current, high detectivity, responsivity, quantum efficiency, and ultrafast response time. In this regard, this review highlights the effect of interfacial engineering to enhance the photodetector performance by adjoining with the active surface. As the interfacial layer, several groups of materials, such as metal oxides, two-dimensional (2D) materials, organic materials, quantum dots (QDs), and self-assembled monolayers (SAMs), have been focused on and discussed their effects on enhancing the device properties through their mechanistic insights. Incorporation of these interfacial layers significantly improves the transportation of the charge carriers with minimal recombination rate, reduces the presence of the dangling bonds and trap states, minimizes the interfacial Schottky contact to improve the charge injection to the electrodes, and broadens the photoresponse range by tuning their band gap and the band alignment. Despite the highlighted challenges of advancing device engineering, surface modifications, and energy efficiency with broadband photodetection, interface engineering remains a crucial strategy for developing high-performance photodetectors, which enables further innovations in optoelectronics devices.