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High‐resolution perovskite quantum dots (PeQDs) arrays printed by electrohydrodynamic (EHD) inkjet printing show great application prospects in fields of micro‐display. Commonly, EHD inkjet requires a polar system for printing but it easily quenches the PeQDs. Meanwhile, the mismatch of solvent parameters causes uneven surface morphology and printing instability. In this work, a morphology uniformization strategy of a nonpolar binary solvent system of 1,3,5‐triethylbenzene and n‐tetradecane is proposed to prepare the didodecyldimethylammonium bromide (DDAB)/PbBr2 passivated PeQDs inks. When the solvent volume ratio is 5:5, the photoluminescence quantum yield (PLQY) of the ink reaches 94.06%. Benefiting from the match of boiling point, surface tension, and dielectric constant of ink, after the EHD inkjet printing, the line width of continuous smooth line arrays is as narrow as 2.0 µm and the coffee effect of dot arrays is well inhibited. Meanwhile, derived from the strong electrostatic interaction between the π‐electron structure of 1,3,5‐triethylbenzene and DDA+, the ink exhibits high stability. Moreover, the high‐resolution logo and miniature quick responsecode by EHD inkjet printing reach 22 718 dpi, far higher than that of the reported micro‐LED. This work paves the way for high‐resolution pixel arrays of micro‐display. [ABSTRACT FROM AUTHOR]

Perovskite quantum dots (PQDs) are a competitive candidate for next‐generation display technologies as a result of their superior photoluminescence, narrow emission, high quantum yield, and color tunability. However, due to poor thermal resistance and instability under high energy radiation, most PQD‐based white light‐emitting diodes (LEDs) show only modest luminous efficiency of ≈50 lm W−1 and a short lifetime of <100 h. In this study, by incorporating cellulose nanocrystals, a new type of QD film is fabricated: CH3NH3PbBr3 PQD paper that features 91% optical absorption, intense green light emission (518 nm), and excellent stability attributed to the complexation effect between the nanocellulose and PQDs. The PQD paper is combined with red K2SiF6:Mn4+ phosphor and blue GaN LED chips to fabricate a high‐performance white LED demonstrating ultrahigh luminous efficiency (124 lm W−1), wide color gamut (123% of National Television System Committee), and long operation lifetime (240 h), which paves the way for advanced lighting technology. [ABSTRACT FROM AUTHOR]