Research on Circularly Polarized Luminescent and Clustering-Triggered Emission Properties of Cholesteryl Benzoate

Abstract

Circularly polarized luminescence (CPL) materials have attracted intensive attention due to their exceptional photophysical properties. However, it has been rarely reported in the field of nontraditional luminescence. It is of great significance to construct circularly polarized luminescent materials with atypical luminescent groups without traditional conjugated structures. Cholesteryl benzoate is a classical cholesteric liquid crystal, and we coincidentally find that it shows clustering-triggered emission behavior in recent studies, which means that cholesteryl benzoate can emit circularly polarized light at the cholesteric liquid crystal phase. Therefore, we synthesized cholesteryl benzoate and studied its photophysical properties in detail. The findings show that cholesteryl benzoate shows triggered emission behavior. The research results suggest that the emission behavior of cholesteric benzoate shows concentration-enhanced emission, aggregation-induced emission (AIE), excitation wavelength dependence, and low-temperature phosphorescence luminescence characteristics. The solid-state circularly polarized luminescence (CPL) property of cholesteryl benzoate quenched by the cholesteric phase was also studied, and the measured luminescence asymmetry factor (glum) could achieve −2.6 × 10–3. In addition, we also simulated the luminescence mechanism of cholesteryl benzoate by theoretical calculation.