Electrohydrodynamically Printed d-f Transition Cerium(III) Complex.

The d-f transition rare earth complexes have recently emerged as a promising candidate for display applications due to the parity-allowed transition, high photoluminescence quantum yield (PLQY), short excited lifetime, and tunable emissions. Besides, inkjet printing has been regarded as an important technique for realizing full-color display. However, inkjet-printed d-f transition rare earth complexes have not been investigated. Herein, for the first time, we explored d-f transition cerium(III) complex 2-Me as the luminescent material by inkjet printing. With 1,2-dichlorobenzene as solvent and polystyrene as an additive, 2-Me film exhibits a similar emission peak and excited-state lifetime with 2-Me powder and a high PLQY of 45%, demonstrating the excellent stability of 2-Me ink. Finally, we suppressed the coffee ring effect and prepared the first inkjet-printed pattern ''HUST'' composed of d-f transition rare earth complex ink with uniform blue fluorescence. Our pioneering work provides a promising alternative for inkjet printing inks.