"Researchers have demonstrated that graphene is highly efficient at generating electrons upon absorbing light, which suggests that the material could be used to make light sensors and perhaps even more efficient solar cells.
Conventional materials that turn light into electricity, like silicon and gallium arsenide, generate a single electron for each photon absorbed. Since a photon contains more energy than one electron can carry, much of the energy contained in the incoming light is lost as heat. Now, new research reveals that when graphene absorbs a photon it generates multiple electrons capable of driving a current. This means that if graphene devices for converting light to electricity come to fruition, they could be more efficient than the devices commonly used today."
The above extract is one of many I have read in the last 12 months regarding carbon in graphene form.
CO2 is often used in plasma processes to create other carbon molecules.
Methane, is now commonly used in plasma furnaces to create diamond coated blades, etc.
Sequestering of CO2 may well turn some atmospheric carbon directly into graphene for solar energy use.
The energy produced by graphene solar arrays may in turn be used to sequester more CO2.
Likewise, methane and coal could be used as direct raw material resources. Any CO2 emissions from processing either, would form more material with plasma recovery methods.
Carbon is plentiful. With new technology, our potentially disastrous affair with fossil fuels may yield a more energy efficient and clean future.
Cheers