Liquid marbles (LMs) are a prominent example of how curiosity-driven research can develop to acquire practical impact, as shown by their use as micro-reactors for materials synthesis. Going beyond chemical reactions, we envisaged that LMs could serve as a platform for designing materials by self-assembly. Here, we explore the cholesteric liquid crystal formation in aqueous hydroxypropyl cellulose solutions inside LMs. By adjusting the periodicity of the cholesteric structure, we realize LMs with structural color that can be tailored anywhere across the visible.
Our LMs respond to various external stimuli by color changes detectable by the naked eye. These results show that LMs are an excellent miniature platform for investigating liquid crystal self-assembly, while highlighting future avenues in developing sustainable multifunctional sensors.
Check out the response of LMs (patterned within a solid polymer matrix) to temperature changes:
Check out the response of LMs to methanol exposure:
Check out the response of LMs to mechanical compression:
You may find the whole article (open access) here.