Efficient emission of quasi-two-dimensional perovskite films cast by inkjet printing for pixel-defined matrix light-emitting diodes

Abstract

Quasi-two-dimensional (quasi-2D) perovskites are promising materials potentially applied in light-emitting diodes (LEDs) due to their high exciton binding energy and efficient emission. However, their luminescent performance is limited by the low-n phases which act as quenching luminescence centers. Here, a novel strategy for eliminating low-n phases is proposed based on the doping of strontium bromide (SrBr2) in perovskites, in which SrBr2 is able to manipulate the growth of quasi-2D perovskites during its formation. The mechanism was reasonably inferred that SrBr2 had readily dissociated strontium ions (Sr2+) in DMSO solvent, and Sr2+ was preferentially adsorbed around [PbBr6]4- through strong electrostatic interaction between them, leading to a controllable growth of quasi-2D perovskites by appropriately increasing formation energy of perovskites. It has been experimentally proven that the growth can almost completely eliminate low-n phases of quasi-2D perovskite films, which exhibited remarkably enhanced photoluminescence (PL). As a result, a high EL efficiency matrix green quasi-2D perovskite-LED (PeLED) with a pixel density of 120 pixels per inch (PPI) fabricated by ink-jet printing technique was achieved, whose peak EQE is 13.9%, which is the most efficient matrix green quasi-2D PeLED so far to our knowledge.

Fused-ring electron acceptors with a macrocyclic side chain

“…S15-S17 and Table S10, ESI †). 56,57 The measured electron mobilities (m e ) of pure MC8-4H, MC8-4F and MC8-4Cl films are 5.96 Â 10 À4 cm 2 V À1 s À1 , 6.64 Â 10 À4 cm 2 V À1 s À1 and 6.22 Â 10 À4 cm 2 V À1 s À1 , suggesting the best electron-transport capability of MC8-4F among the three acceptors. It should be noted that these m e values of acceptors are comparable with those of the state-of-the-art FREAs, 22,30,47,58 suggesting that the compact macrocyclic side chains are benefitted for achieving high m e .…”

A tetracyclic-bislactone-based copolymer donor for efficient semitransparent organic photovoltaics

“…S15, ESI †). [61][62][63] The copolymer shows a good m h of 6.57 Â 10 À4 cm 2 V À1 s À1 . The optical and electrochemical properties of PBDTTPTP were investigated (Fig.…”

Continuous synthesis of all-inorganic low-dimensional bismuth-based metal halides Cs4MnBi2Cl12 from reversible precursors Cs3BiCl6 and Cs3Bi2Cl9 under phase engineering

“…[9][10][11][12][13][14][15][16] Recently, a layered double perovskite with the formula Cs 4 MnBi 2 Cl 12 has attracted much attention due to its unique h111i-oriented crystal structure and excellent optical properties. [17][18][19][20][21] Low-dimensional metal halide perovskites and their analogues have shown great potential in applications for high-performance optoelectronic devices, including photodetectors, light-emitting diodes, fieldeffect transistors, solar cells, photocatalysts, etc. [22][23][24][25][26] It is well known that appropriate ion doping can modify the optical properties of matrix materials, and Mn 2+ , Sb 3+ , Bi 3+ , and Mn 4+ have been widely used as dopants for this purpose.…”