Blue emissive perovskites can be prepared by incorporating chlorine into bromine-based perovskites to tune their bandgap. However, mixed-halide perovskites exhibit intrinsic phase instability, particularly under electrical potential, owing to halide migration. To achieve high-performance blue perovskite-based light-emitting diodes (PeLEDs) with operational stability, organic ammonium cations are used for passivating the anionic defects of the CsPbBr2Cl film. Diphenylpropylammonium chloride (DPPACl), used as a passivating agent, successfully prevents the spectral instability of blue PeLEDs by passivating the Cl− vacancies. Consequently, the blue PeLED prepared with this passivating agent delivers excellent device performance with a maximum external quantum efficiency of 3.03%. Moreover, upon tuning the DPPACl concentration, the PeLED emits stably in the deep-blue spectral region (464 nm) with a half-life time of 420 s. Thus, the use of organic ammonium cation as a passivating agent is an effective strategy for developing high-performance blue PeLEDs with operational stability.
Bibliographical noteFunding Information:
This work was supported by Samsung Research Funding Center of Samsung Electronics under Project Number SRFC‐MA1301‐07.
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All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics