Auger Effect Assisted Perovskite Electroluminescence Modulated by Interfacial Minority Carriers

Perovskite-based light-emitting diodes (PeLEDs) have exhibited promising potential; however, their operational lifetimes are far from expectation. The large bias of the device during operation has been demonstrated as one of main reasons for accelerated device failure. To mitigate such a predicament, interfacial Auger effect (IAE) assisted sub-bandgap voltage electroluminescence (EL) is a potential pathway to decrease the electric field intensity in each functional layer. However, the properties of a desirable IAE are still poorly understood. Herein, the underlying mechanism of IAE based on the injection characteristics of interfacial minority carriers at the Auger effect interface is investigated. Consequently, the prerequisites and the secondary conditions for the realization of IAE are proposed. Taking advantage of IAE assisted EL, the fabricated PeLEDs exhibit ultralow operational voltage, ignorable roll-off, and improved operational stability. The findings in this work not only pave the way toward a feasible approach to enhance the stability of PeLEDs, but also highlight the potential of sub-bandgap voltage EL in future display and lighting applications, especially in series circuits and tandem structures.