A general method for developing high-efficiency organic light-emitting diodes based on aie-active room-temperature phosphorescent polymers
Organic light-emitting diodes (OLEDs) as displays and luminaires have generated enormous attention because of their unique advantages compared to other lighting and display technologies. These include the capacity to fabricate ultra-thin, flexible and transparent devices that additionally have a much lower power consumption. Limited by the electron spin statistics, the maximum internal quantum efficiency (IQE) of conventional fluorescent OLEDs is only 25%. In contrast, thermally activated delayed fluorescence (TADF) can theoretically realize 100% IQE by recruiting triplet excitons and converting them into singlet excitons via reverse intersystem crossing. Most TADF materials must be doped into a rigid host matrix in order to suppress aggregation-caused quenching (ACQ) and other nonradiative processes. An alternative mechanism where 100% IQE can be realized is room temperature phosphorescence (RTP). This proposal targets the development of polymers that are both RTP and show aggregation induced emission (AIE). This permits these materials to be used as high-efficiency emitters in low-cost solution-processed OLEDs. Due to the synergistic effect of AIE, RTP, and polymer, high-efficiency RTP materials can be developed in the amorphous state, a previously undocumented advance in materials development. Through this research proposal, a general road map for simple and high-efficiency PLEDs will be constructed based on AIE-RTP polymers.