Highly Luminescent Liquid Crystals in Aggregation Based on Platinum(II) Complexes
Xingtian Hao, Bijin Xiong, Mingli Ni, Bing Tang, Ying Ma, Haiyan Peng, Xingping Zhou, Ivan I. Smalyukh, Xiaolin Xie
Abstract
Luminescent liquid crystals (LLCs) attract considerable attention because of their broad applications in displays, chemosensors, and anti-counterfeiting. However, it remains challenging to achieve a high luminescence efficiency in LCs because of the common aggregation-caused quenching effect. Herein, we demonstrate a facile approach to designing LLCs with a high quantum yield up to 88% by deliberately tuning the aggregation behavior of platinum(II) complexes with alkoxy chains (CnH2n+1O−). LLCs in hexagonal columnar and rectangular columnar phases are achieved when n = 12 and 16, respectively, as revealed by one-dimensional wide-angle X-ray diffraction and small-angle X-ray scattering. These LLCs are able to not only exhibit strong emission at elevated temperatures but also show attractive reversible vapochromism upon alternative CH2Cl2 and EtOH fuming, which imparts added functions and promises technological utility.