Device Engineering for All-Inorganic Perovskite Light-Emitting Diodes

Abstract

Recently, all-inorganic perovskite light-emitting diodes (PeLEDs) have attracted both academic and industrial interest thanks to their outstanding properties, such as high efficiency, bright luminance, excellent color purity, low cost and potentially good operational stability. Apart from the design and treatment of all-inorganic emitters, the device engineering is another significant factor to guarantee the high performance. In this review, we have summarized the state-of-the-art concepts for device engineering in all-inorganic PeLEDs, where the charge injection, transport, balance and leakage play a critical role in the performance. First, we have described the fundamental concepts of all-inorganic PeLEDs. Then, we have introduced the enhancement of device engineering in all-inorganic PeLEDs. Particularly, we have comprehensively highlighted the emergence of all-inorganic PeLEDs, strategies to improve the hole injection, approaches to enhance the electron injection, schemes to increase the charge balance and methods to decrease the charge leakage. Finally, we have clarified the issues and ways to further enhance the performance of all-inorganic PeLEDs.

Emergence of Impurity-Doped Nanocrystal Light-Emitting Diodes

“…In addition, halide perovskites are found to be a new family of LED emitters because of the outstanding characteristics such as high PLQY, narrow spectrum, and tunable emission in the entire visible region through controlling over anion identity or perovskite size [ 84 , 85 , 86 , 87 , 88 ]. To date, both organic-inorganic hybrid perovskites (e.g., MAPbX 3 , FAPbX 3 ) and all-inorganic perovskites (e.g., CsPbX 3 ) have attracted a great deal of attention from both academic and industrial scientists [ 89 , 90 , 91 ]. Usually, the halide exchange method is exploited to tune the composition post synthetically at mild conditions since anions exhibit good mobility in relatively open perovskite crystal structures, controlling the bandgap [ 92 ].…”

Assessment of Crystalline Materials for Solid State Lighting Applications: Beyond the Rare Earth Elements

“…Such structures have the general structural formula ABX3, where A is a cation such as a methylammonium (MA), formamidinium (FA) or Cs + ; B is a metal (typically Pb 2+ or Sn 2+ ); and X is a halogen (I, Br). Recently, total inorganic perovskites have also been developed, CsPbX 3 (X = I, Br), showing increased properties compared to organic-inorganic halide perovskites (e.g., MAPbBr 3 and FAPbBr 3 ), and for their higher photoluminescence quantum efficiency and thermal stability [25,26].…”

“…MoO 3 -ammonia treated PEDOT:PSS (poly(3,4-ethylenedioxythiophene) polystyrene sulfonate) was used in all-inorganic CsPbBr 3 perovskite LEDs to obtain efficient and stable emission (on the order of a couple of hours of continuous operations), while in [26], the stabilization of the α-CsPbI3 phase was achieved by in situ formations of perovskite nanocrystals (NCs), obtaining 1200 min operation time and shelf stability of over two months, which is much longer than the actual hybrid perovskite-based LED. The hybridization of the structure was further utilized by using polymer nanofiber as the protective layer, where a polymer matrix (polymethylmethacrylate, PMMA) incorporated the CsPbBr 3 quantum dots, improving the stability and maintaining excellent optical properties [27].…”

Advances in Perovskite Light-Emitting Diodes Possessing Improved Lifetime

“…Currently, the maximum EQE of both organic-inorganic hybrid and all-inorganic PeLEDs can exceed 20%, which is comparable to that of state-of-the-art organic LEDs (OLEDs) and Cd-based quantum-dot LEDs (QD-LEDs) [12][13][14][15][16][17]. The full width at halfmaximum (FWHM) of electroluminescence (EL) spectrum in PeLEDs can be as narrow as <20 nm, which is superior to that of advanced OLEDs and Cd-based QD-LEDs [18].…”