Efficient single-component white light emitting diodes enabled by lanthanide ions doped lead halide perovskites via controlling Förster energy transfer and specific defect clearance

Abstract

Currently, a major challenge for metal-halide perovskite light emitting diodes (LEDs) is to achieve stable and efficient white light emission due to halide ion segregation. Herein, we report a promising method to fabricate white perovskite LEDs using lanthanide (Ln3+) ions doped CsPbCl3 perovskite nanocrystals (PeNCs). First, K+ ions are doped into the lattice to tune the perovskite bandgap by partially substituting Cs+ ions, which are well matched to the transition energy of some Ln3+ ions from the ground state to the excited state, thereby greatly improving the Förster energy transfer efficiency from excitons to Ln3+ ions. Then, creatine phosphate (CP), a phospholipid widely found in organisms, serves as a tightly binding surface-capping multi-functional ligand which regulates the film formation and enhances the optical and electrical properties of PeNC film. Consequently, the Eu3+ doped PeNCs based-white LEDs show a peak luminance of 1678 cd m-2 and a maximum external quantum efficiency (EQE) of 5.4%, demonstrating excellent performance among existing white PeNC LEDs from a single chip. Furthermore, the method of bandgap modulation and the defect passivation were generalized to other Ln3+ ions doped perovskite LEDs and successfully obtained improved electroluminescence (EL). This work demonstrates the comprehensive and universal strategies in the realization of highly efficient and stable white LEDs via single-component Ln3+ ions doped PeNCs, which provides an optimal solution for the development of low-cost and simple white perovskite LEDs.

Atomic-scale imaging of ytterbium ions in lead halide perovskites

“…Therefore, various lanthanide ions (Ln 3+/2+ : Ce 3+ , Pr 3+ , Nd 3+ , Sm 3+ , Eu 3+ /Eu 2+ , Gd 3+ , Tb 3+ , Dy 3+ , Ho 3+ , Er 3+ , Tm 3+ , Yb 3+ /Yb 2+ , etc.) have been incorporated into perovskites to notably improve their performances and broaden their applications via single-, co-, or tri-doping, respectively (26)(27)(28)(29)(30)(31)(32)(33). Many landmark works have been achieved by the marriage of lanthanide ions with perovskites.…”

Manipulating Ionic Behavior with Bifunctional Additives for Efficient Sky‐Blue Perovskite Light‐Emitting Diodes

“…Metal-halide perovskites (MHPs) are gaining enormous attention owing to several excellent electroluminescence (EL) attributes, [1][2][3][4][5] and perovskite light-emitting diodes (PeLEDs) are developing as a competitive candidate for high-definition and wide-color-gamut displays. [6][7][8][9][10] However, as an indispensable part of full-color pixels, blue PeELDs still lags far behind the other counterparts emitting longer wavelength, especially in EL efficiencies. [11][12][13][14][15][16][17] Considering the requirements of display commercialization, more efforts have to be devoted for constructing highperformance blue MHPs and PeLEDs.…”

Tunable and Efficient Photoluminescence of Lanthanide-Doped Cs2NaScCl6 Double Perovskite Single Crystals toward Multifunctional Light-Emitting Diode Applications

“…Ion doping is an effective strategy to improve the optical properties of metal halide perovskite materials. − For instance, Mn 2+ and tervalent lanthanide (Ln 3+ ) ions were used to substitute Pb 2+ ions partly in the lead halide perovskite, realizing double emission of the excitons and doped ions. − Na + ions were alloyed into the Cs 2 AgInCl 6 single crystals and improved the photoluminescence quantum yield (PLQY) of the samples by breaking the parity–forbidden transition of dark STEs . Recently, impurity dopants including Mn 2+ , In 3+ , Yb 3+ , Er 3+ , Sm 3+ , Tb 3+ , and Eu 3+ have been tried to dope in lead-free halide DP nanocrystals (NCs) to endow desirable optical properties in these double perovskite NCs. − However, Ln 3+ ions doping into DPNCs do not exhibit high emission intensity.…”