The reason trees are our friends is that they take CO2 out of the atmosphere and turn it into things that are less bad for the environment and much more useful to us, namely wood and fruit and oxygen and stuff. A novel new chemical reaction promises to do the same sort of thing, transforming CO2 straight into a semiconductor, fertilizer and a big pile o' energy.
Professor Yun Hang Hu, a materials scientist at Michigan Technological University, has come up with a way to react carbon dioxide with Li3N (a lithium-nitrogen compound) that generates a bevy of cool stuff while simultaneously getting rid of the CO2 entirely. Three things come out of the reaction: you get amorphous carbon nitride (C3N4), which is a semiconductor. You get lithium cyanamide (Li2CN2), which is a precursor to fertilizers. And also, you get energy. Lots of it.
The reaction has to be run at about 330 degrees Celsius, but as soon as it kicks off, the temperature skyrockets by a factor of three to about 1,000 degrees Celsius, which is approximately equivalent to the temperature of lava flowing out of a volcano. This is easily enough energy to harvest to make up for the initial reaction temperature, with enough left over to generate an appreciable amount of power.
As the researchers point out, the fact that this reaction converts CO2 from a gas into a solid is useful enough by itself, since it sequesters the CO2 away and keeps it out of the atmosphere. The other side-effects of the reaction are just gravy, but gravy that has the potential to be lucrative enough to lead to a new industrial-scale process that helps to mitigate climate change.