NDLI: Silicon-based electron-transport materials with high thermal stability and triplet energy for efficient phosphorescent OLEDs

Please wait, while we are loading the content...

Silicon-based electron-transport materials with high thermal stability and triplet energy for efficient phosphorescent OLEDs

Content Provider	Semantic Scholar
Author	Yi, Seungjun Kim, Jin-Hyoung Bae, Woori Han, Won-Sik Kang, Sang Ook
Copyright Year	2015
Abstract	Abstract A series of electron transporting materials was designed and used in organic light-emitting diodes (OLEDs), exhibiting green phosphorescence. We used the tetrahedral structural motif of silicon atom, which annulated with the 1,2-diphenyl-benzoimidazole (DBI) units in its periphery ( 1 – 4 ) and their thermal, photophysical, and electrochemical properties were investigated. Among the series, the X-ray crystal structure of compound 1 was obtained and investigated. Photophysical and electrochemical properties showed that their LUMO levels can be slightly tuned as increasing number of DBI units and enhancing the electron injection capability. Furthermore, thermal stability correlated well with an increase in the number of DBI units, showing a gradual increase in T g values in the range of 100–141 °C. The electron-only devices (EOD) based on compounds 2 and 3 were fabricated; EOD device with compound 3 showed higher current densities at the same voltages, indicating higher electron transport (ET) capability compared to compound 2 . The electron mobilities (μ) of compounds 2 and 3 were estimated as 1.93 × 10 −5 cm 2 /V and 3.67 × 10 −5 cm 2 /V at 1 MV/cm, respectively. We further investigated the excellent ET property of compound 3 via the phosphorescent OLEDs in which the electron-transporting material (ETM) was coupled with the green emitter, Ir(ppy) 3 . Finally, we compared it with the device based on compound 2 . The OLEDs device with compound 3 exhibited maximum current and external quantum efficiencies of 62.8 cd/A and 18.0%, respectively, with a small efficiency roll-off at high current densities.
Starting Page	126
Ending Page	132
Page Count	7
File Format	PDF HTM / HTML
DOI	10.1016/j.orgel.2015.08.029
Volume Number	27
Alternate Webpage(s)	http://www.imid.or.kr/2015/files/L_14_1008.PDF
Alternate Webpage(s)	https://doi.org/10.1016/j.orgel.2015.08.029
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in