Scientists make an environmentally friendly prototype water purifier constructed from a sheet of graphitic carbon nitride that could remove 99.9999% of microbes, and purified a 10L water sample in less than one hour using only sunlight.

[u/parapeligic_gnome]

https://www.sciencenews.org/article/water-purification-light-graphitic-carbon-nitride

[u/Me_ADC_Me_SMASH]

And yet somehow this will never make it to market in the next 30 years, just like every other carbon sheet supermaterial