Recent Progress on Organic Exciplex Materials with Different Donor-Acceptor Contacting Modes for Luminescent Applications

Recently organic exciplex materials have captured considerable attention due to the promising luminescent applications in organic optical waveguides, lasers, nonlinear optics, light-emitting diodes and even light-emitting transistors. The emission features together with other optoelectronic properties can be tailored via intermolecular charge-transfer interactions by the judicious selection of various component materials. In this review, first we will discuss the formation mechanism and emission process of exciplex under photoexcitation or electrical excitation, which will shed light on realizing high-efficiency luminescence and generating new optical functions. Next, we will mainly introduce the various organic exciplex materials in terms of donor–acceptor contacting modes (cocrystals, interface, blend, porous coordination, space-limitation) and their potential applications in optoelectronics devices. Finally, we will present the current obstacles and limitations of organic exciplex materials as well as their prospects for future research.