Fabrication of Highly Efficient Perovskite Nanocrystal Light-Emitting Diodes via Inkjet Printing

Abstract

As an effective manufacturing technology, inkjet printing is very suitable for the fabrication of perovskite light-emitting diodes in next-generation displays. However, the unsatisfied efficiency of perovskite light-emitting diode created with the use of inkjet printing impedes its development for future application. Here, we report highly efficient PeLEDs using inkjet printing, with an external quantum efficiency of 7.9%, a current efficiency of 32.0 cd/A, and the highest luminance of 2465 cd/m2; these values are among the highest values for the current efficiency of inkjet-printed PeLED in the literature. The outstanding performance of our device is due to the coffee-ring-free and uniform perovskite nanocrystal layer on the PVK layer, resulting from vacuum post-treatment and using a suitable ink. Moreover, the surface roughness and thickness of the perovskite layer are effectively controlled by adjusting the spacing of printing dots. This study makes an insightful exploration of the use of inkjet printing in PeLED fabrication, which is one of the most promising ways for future industrial production of PeLEDs.

Progress on Inkjet Printing Technique for Perovskite Films and Their Optoelectronic and Optical Applications

“…In 2022, Ye et al 93 dispersed the prepared perovskite nanocrystals in the binary ink system of dodecane and octane and replaced the toluene in previous study with octane to eliminate the damaging effect of the ink on the underlying PVK layer. At the same time, the contact angle between the highviscosity ink and PVK was small.…”

Fully Inkjet‐Printed Green‐Emitting PEDOT:PSS/NiO/Colloidal CsPbBr3/SnO2 Perovskite Light‐Emitting Diode on Rigid and Flexible Substrates

“…[ 26 ] However, spin coating is not suitable for large=‐area fabrication, does not provide spatial resolution, and only ≈2% of the solution dropped contributes to the ultimate thin film. [ 27 ] Among industrially relevant fabrication techniques, inkjet printing (IP) is one of the powerful upscalable techniques. [ 28 ] Hermerschmidt et al published the first inkjet‐printed MAPbBr 3 PeLED whose maximum luminance was 4000 cd m −2 for devices based on PEDOT:PSS with different amounts of KCl as an additive to tune the crystallization process of the HP.…”

“…[34] On the contrary, a binary solvent combination was suggested to improve a FAPb 0.7 Sn 0.3 Br 3 -based HP-NCs ink, which resulted in an EQE of 7.9%. [37] Therefore, most of the improvement in inkjet-printed PeLEDs has been achieved through exploitation of passivation layers, [30] by introducing additives [29,38] and/ or using cosolvents. [27,34,35] It is worth noting that all the aforementioned precedents on IJP PeLEDs (except one, Table S1, Supporting Information) are based on the inkjet deposition of only the light-emitting layer, that is, MHP.…”

“…[37] Therefore, most of the improvement in inkjet-printed PeLEDs has been achieved through exploitation of passivation layers, [30] by introducing additives [29,38] and/ or using cosolvents. [27,34,35] It is worth noting that all the aforementioned precedents on IJP PeLEDs (except one, Table S1, Supporting Information) are based on the inkjet deposition of only the light-emitting layer, that is, MHP. Among them, only two works [34,39] involved all-inorganic HP-NCs (CsPbBr 3 ).…”

Editorial for the Special Issue on Quantum Dots Frontiers

“…The main challenge remaining is achieving efficient and stable QLED with blue emission. Notably, the QDs for lighting and display applications are mainly referred to CdSe QDs, InP QDs (mostly merged as core-shell structured QDs, and the alloyed QDs) [ 3 , 5 , 6 , 7 ], and perovskite nanocrystals [ 8 , 9 , 10 ].…”