Colloidally stable, magnetoresponsive liquid crystals based on clay nanosheets

Abstract

Liquid crystalline materials found numerous applications in modern technologies due to their ability to respond to external fields. In this context, ferronematic liquid crystals are fascinating because they offer a response to weak magnetic fields in addition to electrical fields. Nevertheless, the synthesis of stable ferronematic liquid crystals represents a challenge for colloidal and synthetic chemists. In this work, we present a straight-forward strategy for directly incorporating presynthesized magnetic nanoparticles into every other interlayer of synthetic 2 : 1 layered silicates, which subsequently can be swollen to nematic phases simply by immersion into water, offering almost infinite stability. The resulting ferronematic suspension shows a sensitive response to magnetic fields. Moreover, the synthetic strategy is highly modular, enabling for variations of the magnetic nanosheets that allow for tuning the interaction between nanosheets and blocking temperature.