High-performance solution-processed OLEDs utilizing a nonplanar terdentate chloroplatinum emitter

Platinum complexes are one of the most promising emitters for organic light-emitting diodes (OLEDs) and they have been studied for decades. However, it is still challenging to realize high-performance solution-processed OLEDs by using the platinum complex as an emissive dopant. Herein, a nonplanar terdentate [Pt(N<^>C<^>N)Cl] emitter (Pt1) with good solubility and film-forming ability, ultrahigh photoluminescence quantum yield (98% in PMMA film), and short excited-state lifetime (1.5 mu s in solution) is presented to achieve this goal. This complex is designed and synthesized by using a nonplanar ligand strategy. Solution-processed OLEDs of Pt1 are successfully fabricated to show a maximum external quantum efficiency (EQEmax) of 16.14%, a maximum current efficiency (CEmax) of 46.36 cd A-1, a maximum luminance (Lmax) of 13990 cd m-2, and operating half-lifetime (LT50) of 288 min, respectively, representing the highest performance recorded so far based on the terdentate platinum complexes. More importantly, the large-area (144 mm2) OLEDs of Pt1 with high EQEmax of 10.28% and uniform luminance of 8076 cd m-2 have been achieved, indicating a high potential of Pt1 for commercial applications.