A two-dimensional metal oxide material called titanate nanosheets has remained pretty much off the radar of flatland materials expected to transform the worlds of electronics and optoelectronics. Its biggest claim to fame has been that it is pretty effective at cleaning up contaminants.

However, it would seem that titanate nanosheets history of being overlooked  in the catalogue of 2D materials may have come to an end thanks to a serendipitous discovery by researchers in Japan.

Researchers at the RIKEN Center for Emergent Matter Science in Japan were experimenting with the material to see if they could get the nanosheets to break into more uniform pieces rather than the varied sizes they typically take. Unfortunately, they weren’t able to solve this problem. But they did discover that when the material was centrifuged in water, it changed from being transparent to taking on a deep purple color.

The resulting liquid, which the researchers have dubbed ‘photonic water’, is able to reflect light over the widest range of wavelengths ever reported: from the ultraviolet to the infrared. The researchers discovered that the photonic water changes color when exposed to chemical or magnetic forces that adjust the alignment of internal stacks of reflective nanosheet crystals. The discovery could ultimately lead to applications in telecommunications and lasers.

“When my student Koki Sano first told me about the color change on centrifugation, I couldn’t believe it,”…[Read more]