High-Efficiency Solution-Processed Organic Light-Emitting Diodes with Tetradentate Platinum(II) Emitters

Gang Cheng; Yoonhyun Kwak; Wai-Pong To; Tsz-Lung Lam; Glenna So Ming Tong; Man-Ki Sit; Shaolong Gong; Byoungki Choi; Wha Il Choi; Chuluo Yang; Chi-Ming Che

doi:10.1021/acsami.9b11715

High-Efficiency Solution-Processed Organic Light-Emitting Diodes with Tetradentate Platinum(II) Emitters

ACS Appl Mater Interfaces. 2019 Dec 4;11(48):45161-45170. doi: 10.1021/acsami.9b11715. Epub 2019 Nov 21.

Authors

Gang Cheng^{1

2}, Yoonhyun Kwak³, Wai-Pong To^{1

2}, Tsz-Lung Lam², Glenna So Ming Tong², Man-Ki Sit², Shaolong Gong⁴, Byoungki Choi³, Wha Il Choi⁵, Chuluo Yang⁴, Chi-Ming Che^{1

2}

Affiliations

¹ HKU Shenzhen Institute of Research and Innovation , Shenzhen 518053 , P. R. China.
² State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, and Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , P. R. China.
³ Samsung Electronics, Organic Material Lab, SAIT , 130 Samsung-ro , Yeongtong-gu, Suwon-si , Gyeonggi-do 16678 , Korea.
⁴ Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Department of Chemistry , Wuhan University , Wuhan 430072 , P. R. China.
⁵ Samsung Electronics, Samsung Research Funding & Incubation Center for Future Technology Seoul R&D Campus , Umyeon dong 33, Seongchon-gil , Seocho-gu, Seoul 06765 , Korea.

PMID: 31718137
DOI: 10.1021/acsami.9b11715

Abstract

The realization of high-efficiency solution-processed organic light-emitting diodes (OLEDs) using phosphorescent tetradentate Pt(II) emitters and bipolar organic hosts is demonstrated in this work. To investigate the effect of organic host on the platinum dopant, the performances of solution-processed Pt-OLEDs with various combinations between four tetradentate Pt(II) emitters, including two newly developed tetra-Pt-S2 and tetra-Pt-S3 and three bipolar organic hosts m-TPAPy, o-TPAPy, and o-CzPy, have been analyzed and compared. Among the tetradentate Pt(II) complexes studied in this work, tetra-Pt-S3 exhibited the best electroluminescent performance attributable to its bulky molecular scaffold structure, high emission quantum yield, and good solubility in common organic solvents. High external quantum efficiencies (EQEs) of up to 22.4% were achieved in the solution-processed OLED with tetra-Pt-S3 emitter and m-TPAPy host at the dopant concentration of 4 wt %. At a high luminance of 1000 cd m^-2, the EQE of this device decreased slightly to 21.0%.

Keywords: bipolar organic host; high efficiency; organic light-emitting diodes; platinum complexes; solution process.