Luminescent tetraphenylethene-substituted silanes

Zhao, Zujin; Chen, Shuming; Lam, Jacky W. Y.; Chan, Carrie Y. K.; Jim, Cathy K. W.; Wang, Zhiming; Wang, Chunlei; Lu, Ping; Kwok, Hoi Sing; Ma, Yuguang; Tang, Ben Zhong

doi:10.1351/PAC-CON-09-09-15

Pure Appl. Chem., 2010, Vol. 82, No. 4, pp. 863-870

http://dx.doi.org/10.1351/PAC-CON-09-09-15

Published online 2010-02-26

Luminescent tetraphenylethene-substituted silanes

Zujin Zhao¹, Shuming Chen², Jacky W. Y. Lam¹, Carrie Y. K. Chan¹, Cathy K. W. Jim¹, Zhiming Wang³, Chunlei Wang³, Ping Lu^1,3, Hoi Sing Kwok², Yuguang Ma³ and Ben Zhong Tang^2,1,4,5*

¹ Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
² Center for Display Research, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
³ State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, China
⁴ Department of Polymer Science and Engineering, Key Laboratory of Macromolecular Synthesis and Functionalization of the Ministry of Education of China, Zhejiang University, Hangzhou 310027, China
⁵ William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China

Abstract: Tetraphenylethene (TPE)-substitued silanes [(Ph₄C=C)_mSi(Ph)_n, m = 3–1, n = 3–1] are designed and synthesized, and their optical, thermal, and electrochemical properties are studied. Whereas they are nonluminescent in solutions, they become highly emissive when aggregated in poor solvents (such as water) or fabricated into thin films, demonstrating a novel phenomenon of aggregation-induced emission (AIE). Their amorphous films exhibit high fluorescence quantum yields (54.6–63.7 %). They enjoy high thermal stability with 5 % weight loss occurring at 320–420 °C. Multilayer electroluminescence (EL) devices (ITO/NPB/emitter/TPBi/LiF/Al) utilizing the silanes as emitting layers are fabricated, which give deep blue EL with maximum luminance and external quantum efficiency of 5672 cd/m², and 1.6 %, respectively.