Improved Electroluminescence Performance of Perovskite Light-Emitting Diodes by a New Hole Transporting Polymer Based on the Benzocarbazole Moiety

Abstract

A new hole-transporting material, poly-2-(9Hcarbazol-9-yl)-5-(4-vinylphenyl)-5H-benzo[b]carbazole (PBCZCZ), was developed for perovskite light-emitting diodes (PeLEDs). This polymer, which is based on the benzocarbazole moiety, has good solubility in common solvents and enabled the fabrication of highly efficient multilayer perovskite devices. It has excellent film morphology and a high hole mobility of 3.67 × 10 −5 cm 2 V −1 s −1 , which made it possible to vary the device configuration. Green and sky-blue perovskite PeLEDs using PBCZCZ as the hole-transporting layer had current efficiencies and external quantum efficiencies (EQEs) of 43.90 cd A −1 and 8.67% for the green device and 9.07 cd A −1 and 4.04% for the skyblue device, respectively. The EQE of the green PeLEDs was about 2.5 times higher and that of the sky-blue PeLEDs was about 3 times higher than the device made with the commercial HTL of poly(9-vinylcarbazole) (PVK). The operational device lifetimes of the green and sky-blue PeLEDs made with PBCZCZ were about 4.1 and 4.8 times higher than the PVK-containing device, respectively.

Exploring the molecular electronic device applications of synthetically versatile silicon pincer complexes as charge transport and electroluminescent layers

“…The Si(bzimpy) 2 parent compound and complex 4 containing the methoxy and methylated benzimidazole ligand, Si(MeOMe 2 bzimpy) 2 , exhibit an absorption range and (E) in between complexes 2 and 3. The 29 Si NMR peak also indicates a an Please do not adjust margins Please do not adjust margins upfield shift (more electron shielding) in agreement with the overall electron donating ability of the substituents and the experimentally determined reduction potentials. Singlet fluorescence emission spectra of the complexes in solution also show the HOMO/LUMO gap energy trend with a peak fluorescence range between 460 and 525 nm.…”

“…Measuring, optimizing, and establishing structure relationships electron and hole mobilities is critical for designing efficient devices regardless of the organic material function. Organic semiconductors also find uses in a variety of OPV and OLED devices specifically as a hole conduction layer (HTL), [28][29] or as the electron conduction layer (ETL). 30 To demonstrate the full versatility of these complexes, devices incorporating the derivatives were constructed using vacuum-deposited thin films of the derivatives.…”

Interface engineering improves the performance of green perovskite light-emitting diodes

“…Furthermore, polycrystalline perovskite films spin-coated on the surface of the pristine PEDOT:PSS generally have a poor morphology, which further hinders device performance. [20][21][22] To tackle this issue, PEDOT:PSS modification is a prospective way to adjust the work function and reduce defects. Liu et al achieved a 133% improvement in current efficiency by adding sodium dodecylbenzene sulfonate (SDBS) into PEDOT:PSS, which greatly reduced the contact barrier between the HTL and emissive layer, and then boosted the carrier injection efficiency.…”

Organic–Inorganic Hybrid Device with a Novel Deep-Blue Emitter of a Donor–Acceptor Type, with ZnO Nanoparticles for Solution-Processed OLEDs

“…The synthesis methods of TDBA, 1 , 2 , 3 , and 4 , which are used in the present work as intermediate compounds ( Figure S1 ), have been reported elsewhere [ 24 , 40 ]. The 1 H and 13 C nuclear magnetic resonance (NMR) data are presented in Figures S11–S17 .…”