Nanotubes convert CO2 and sunlite into methane!

''"Instead we can collect the waste out of the smoke stack, put it though a converter, and presto, use sunlight to change [CO2] back into fuel."
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The scientists have created thin membranes that cover either 3.8 or 15.5 square inches. So far, those membranes have produced an estimated 66 gallons of methane, said Grimes.'' [source]