Tetradentate Cyclometalated Platinum(II) Complexes for Efficient and Stable Organic Light-Emitting Diodes

As one of the most important phosphorescent emitters, tetradentate cyclometalated platinum(II) complexes have attracted much attention in recent years, because of the high luminescent efficiency, emission spectra, and color tuned easily, especially for the development of high-efficient deep-blue and “pure” blue emitters and single-doped white organic light-emitting diodes (OLEDs). Also, some platinum(II)-based OLEDs exhibited superior operational stability, indicating their potentials in full-color display and solid-state lighting applications. In this chapter, we will introduce the recent advances of the tetradentate cyclometalated platinum(II) complexes, including pyrazole, N-heterocyclic carbene, imidazole and pyridine-based complexes, molecular design, photophysical properties, and some of their device performances.