Physical properties of liquid crystals doped with CsPbBr<sub>3</sub> quantum dots
Xuelian Liu, Xiang Xia, Le Yang, Jun Zhu, Miao Xu, Guobing Zhang, Guo Xia, Longzhen Qiu, Hongbo Lu
Abstract
CsPbBr3/SiO2 perovskite quantum dots (PQDs), which exhibit good stability in water, air, and light, are synthesised using the water-trigger method. Due to the interaction between the long alkyl ligands of the PQDs and the liquid crystal, the liquid-crystal molecules prefer to align perpendicular to the surface of the PQDs, which disturbs the liquid crystal order and decreases its clearing point. The effect of CsPbBr3/SiO2 PQDs on the electro-optical properties and physical parameters of a nematic liquid crystal are investigated. The dielectric anisotropy (Δε) and splay elastic constant (K11) decrease substantially with increasing concentration of PQDs. PQDs, which are doped into the liquid crystal, can effectively reduce the threshold voltage (Vth), which opens possibilities to reduce energy consumption in many optoelectronic devices.