New graphene water filter

One encouraging aspect of technology is new low-cost methods of water filitration. Here's a story about a new form of water filter derived from graphene, which has microscopic channels that allow water to pass but block pollutants. Ultimately, I suspect methods like these will be adapted for backpackers and homesteaders.

https://www.yahoo.com/news/graphene-film-makes-dirty-water-120100709.html

Looks like it comes with a price: (and doesn't everything!)

Graphene: miracle material and potentially potent pollutant

Explosions may be the answer to mass-producing graphene

Though there is an amazing list of potential uses: super-storage batteries, heart monitors, super computer chips, solar panels that also generate from raindrops...

But why use an expensive, energy-intensive, dangerous nanoproduct when any village can make activated carbon out of waste woods with an old oildrum and tin clippers?