Please use this identifier to cite or link to this item: http://localhost:8080/xmlui/handle/123456789/3539
Title: Solution Processable Deep-Red Phosphorescent Pt(II) Complex: Direct Conversion from Its Pt(IV) Species via a Base-Promoted Reduction
Authors: Allison, I
Lim, H
Shukla, A
Ahmad, V
Hasan, M
Deshmukh, K
Wawrzinek, R
McGregor, S K M
Clegg, J K
Divya, V V
Govind, C
Suresh, C H
Karunakaran, V
Unni, K N N
Ajayaghosh, A
Namdas, E B
Lo, S C
Keywords: deep red phosphorescence
solution processed
rigid tetradentate
platinum complex
base-promoted reduction
Issue Date: 21-Jun-2019
Publisher: American Chemical Society
Citation: ACS Applied Electronic Materials; 1(7):1304-1313
Abstract: Color purity is a critical prerequisite for full color displays. Creation of deep-red phosphorescent materials with high PLQYs is particularly challenging because of the “energy gap law”. Simultaneously achieving high yielding solution processable Pt(II) complexes further complicates this challenge. In this report, we developed a high-yielding synthetic route to a solution processable/deep-red Pt(II) complex with a rigid tetradentate structure, in which we identified an octahedral Pt(IV) complex as a major side product formed under the standard complexation conditions. We managed to effectively transform the octahedral Pt(IV) species into a highly luminescent deep-red square-planar Pt(II) complex through a base-promoted reduction. The Pt(II) complex was found to exhibit high solution and blend film PLQYs. X-ray crystal structure and DFT calculations of the Pt(II) complex showed that perpendicular orientation of molecular dipoles enhanced the luminescence properties. In neat films, there was no luminescence enhancement due to interdigitation of the attached hexyloxy tails, preventing strong Pt···Pt interactions in the solid state. Solution-processed OLEDs based on the Pt(II) complex showed a low turn-on voltage of 3.3 V (at 1 cd/m2) with a maximum brightness of 2000 cd/m2 and a maximum EQE of ≈6% (4% at 100 cd/m2). A narrow electroluminescence with a full width at half-maximum of ≈50 nm was observed with a peak at 623 nm and deep-red emission with 1931 CIE coordinates of (0.65, 0.35). Transient electroluminescence measurements were used to investigate the EQE roll-off of the OLEDs.
Appears in Collections:2019

Files in This Item:
File Description SizeFormat 
Solution Processable Deep Red_Ilene Allison_Applied Electronic Materials.pdf
  Restricted Access
2.16 MBAdobe PDFView/Open Request a copy

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.