Achieving Deep-Blue Thermally Activated Delayed Fluorescence in Nondoped Organic Light-Emitting Diodes through a Spiro-Blocking Strategy

Jiancheng Rao; Chenyang Zhao; Yanping Wang; Keyan Bai; Shumeng Wang; Junqiao Ding; Lixiang Wang

doi:10.1021/acsomega.8b03296

Achieving Deep-Blue Thermally Activated Delayed Fluorescence in Nondoped Organic Light-Emitting Diodes through a Spiro-Blocking Strategy

ACS Omega. 2019 Jan 23;4(1):1861-1867. doi: 10.1021/acsomega.8b03296. eCollection 2019 Jan 31.

Authors

Jiancheng Rao^{1

2}, Chenyang Zhao^{1

3}, Yanping Wang⁴, Keyan Bai^{1

2}, Shumeng Wang¹, Junqiao Ding^{1

3}, Lixiang Wang^{1

3}

Affiliations

¹ State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.
² University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
³ University of Science and Technology of China, Hefei 230026, P. R. China.
⁴ School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, P. R. China.

Abstract

A deep-blue thermally activated delayed fluorescence (TADF) emitter TXADO-spiro-DMACF has been reported for nondoped organic light-emitting diodes (OLEDs) by integrating an appropriate blocking unit with the donor (D)-acceptor (A)-donor (D)-type TADF emitter via a spiro linkage. Benefiting from the characteristic perpendicular arrangement, the intermolecular interactions are expected to be weakened to some degree. As a result, TXADO-spiro-DMACF shows a very small bathochromic shift of 8 nm associated with a narrowed full width at half maximum of 54 nm on going from solution to the film. The corresponding nondoped device successfully achieves a bright deep-blue emission, revealing Commission Internationale de l'Eclairage coordinates of (0.16, 0.09) and a peak external quantum efficiency of 5.3% (5.3 cd/A, 5.9 lm/W). The results clearly indicate that spiro-blocking is a promising strategy to develop deep-blue TADF emitters capable of nondoped OLEDs.