Iqbal Amir, Urbanska Magdalena, Dąbrowski Roman S, Kumar Sandeep, Dhar Ravindra
Soft Materials Research Laboratory, Centre of Material Sciences, Institute of interdisciplinary Studies, University of Allahabad, Allahabad-211002, India.
Institute of Applied Sciences and Chemistry, Military University of Technology, Warsaw 00-908, Poland.
Soft Matter. 2023 Dec 6;19(47):9293-9307. doi: 10.1039/d3sm01226c.
We investigated the impact of carbon quantum dots (CQDs) of sizes ∼2-5 nm in a room temperature tri-component fluorinated antiferroelectric liquid crystal (AFLC) mixture. The synthesised CQDs have been characterised by high-resolution transmission electron microscopy and X-ray diffraction spectroscopy. An increase in the transition temperature and enthalpy to the isotropic liquid phase indicates stabilization of the AFLC mixture in the presence of CQDs. The dielectric studies have been carried out in the frequency range of 1 Hz-40 MHz under the planar anchoring conditions of the molecules. An appreciable increase in the permittivity, dielectric strength, and conductivity has been observed owing to the existence of sp/sp hybridization in the CQDs which form a strong coupling and develop a dipolar ordering in the systems. Various relaxation frequencies were increased with the incarceration of CQDs in the AFLC mixture. Overall, the different studies suggest that the doped CQDs are very well settled in between the host molecules without disturbing the molecular ordering of the hosts. Such results are encouraging and reveal the potential applicability of the CQD doped systems to produce highly efficient tuneable optical devices and other multifaceted applications.
我们研究了尺寸约为2 - 5纳米的碳量子点(CQDs)对室温下三元氟化反铁电液晶(AFLC)混合物的影响。合成的碳量子点已通过高分辨率透射电子显微镜和X射线衍射光谱进行了表征。向各向同性液相转变的温度和焓的增加表明在碳量子点存在的情况下AFLC混合物得到了稳定。在分子的平面锚定条件下,在1赫兹至40兆赫的频率范围内进行了介电研究。由于碳量子点中存在sp/sp杂化,形成了强耦合并在系统中产生偶极有序,因此观察到介电常数、介电强度和电导率有明显增加。随着碳量子点被引入AFLC混合物中,各种弛豫频率增加。总体而言,不同的研究表明,掺杂的碳量子点很好地嵌入主体分子之间,而不会干扰主体分子的有序排列。这些结果令人鼓舞,并揭示了碳量子点掺杂系统在生产高效可调谐光学器件和其他多方面应用中的潜在适用性。