Nanoparticles: complex and multifaceted additives for liquid crystals

In this review article we provide an overview of our work on nanoparticle-doped liquid crystal phases including nematic, smectic and columnar phases. Over the past years, we have shown that nanoparticles can serve as alignment mediators and chiral dopants for nematic liquid crystals all while affecting the electro-optic parameters of the nematic host. We have started to establish some size–property, core material–property and capping agent–property relationships in these composites, which show that nanoparticle/liquid crystal compatibility (i.e. miscibility) and segregation effects need to be finely tuned for a particular application of nanoparticles as dopant for nematic liquid crystals. Finally, we also discuss the self-assembly and liquid crystal phase formation of nanoparticles and our own research on bent-core liquid crystal-decorated gold nanoparticles.