Functionalized Zinc Porphyrins with Various Peripheral Groups for Interfacial Electron Injection Barrier Control in Organic Light Emitting Diodes

Abstract

Here, we use a simple and effective method to accomplish energy level alignment and thus electron injection barrier control in organic light emitting diodes (OLEDs) with a conventional architecture based on a green emissive copolymer. In particular, a series of functionalized zinc porphyrin compounds bearing π-delocalized triazine electron withdrawing spacers for efficient intramolecular electron transfer and different terminal groups such as glycine moieties in their peripheral substitutes are employed as thin interlayers at the emissive layer/Al (cathode) interface to realize efficient electron injection/transport. The effects of spatial (i.e., assembly) configuration, molecular dipole moment and type of peripheral group termination on the optical properties and energy level tuning are investigated by steady-state and time-resolved photoluminescence spectroscopy in F8BT/porphyrin films, by photovoltage measurements in OLED devices and by surface work function measurements in Al electrodes modified with the functionalized zinc porphyrins. The performance of OLEDs is significantly improved upon using the functionalized porphyrin interlayers with the recorded luminance of the devices to reach values 1 order of magnitude higher than that of the reference diode without any electron injection/transport interlayer.

Effects of methoxy group(s) on D-π-A porphyrin based DSSCs: efficiency enhanced by co-sensitization

“…Porphyrins are widely present in biological systems and have shown impressive performance for many optoelectronic applications, such as organic light-emitting diodes, hole-transporting materials for perovskite solar cells, sensitizers for photodynamic therapy, and DSSCs. 8–14…”

Solution-Processable meso-Triarylamine Functionalized Porphyrins with a High Mobility and ON/OFF Ratio in Bottom-Gated Organic Field-Effect Transistors

“…All the porphyrins 5a−e exhibit a typical intense Soret band at a wavelength of 380−480 nm attributed to the second excited state S 0 to S 2 transition. 21 Less intense Q-bands are observed in the range of 550−750 nm. 22 Both Soret and Q bands arise due to the π−π* transition.…”

Electron configurations at 3d orbital of metal ion determining charge transition process in memory devices

“…The core position of porphyrin ring provides the ability to complex up to 56 different metal elements [29], and its electronic structure could be regulated by simply varying the central metal ion to achieve expected functions. For example, the capacity of zinc (Zn) ion to raise the electronic density of porphyrin ring endows the Zn porphyrins with the applications for solar cells [30][31][32] and organic light emitting diodes (OLEDs) [33][34][35]. The high spin state and coordination effect of manganese (Mn) ion make Mn porphyrins widely used in simulation of cytochrome P450 [36][37][38] and sensors [39][40][41].…”