According to Yasuhiro Ishida, head of the Emergent Bioinspired Soft Matter Research Team, the work began from a surreptitious discovery, that when titanate nano-sheets are suspended in an aqueous colloidal dispersion, they align themselves face-to-face in a plane when subjected to a strong magnetic field. The field maximizes the electrostatic repulsion between them and entices them into a quasi-crystalline structure. They naturally orient themselves face to face, separated by the electrostatic forces between them.
To create the new material, the researchers used the newly discovered method to arrange layers of the sheets in a plane, and once the sheets were aligned in the plane, fixed the magnetically induced structural order by transforming the dispersion into a hydrogel using a procedure called light-triggered in-situ vinyl polymerization. Essentially, pulses of light are used to congeal the aqueous solution into a hydrogel, so that the sheets could no longer move.
By doing this, they created a material whose properties are dominated by electrostatic repulsion, the same force that makes our hair stand end when we touch a van generator.
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