Carbon?

Everybody knows that we are in a huge environmental crisis about there being too much carbon dioxide in the air. One way scientists are trying to solve this problem is by changing the carbon dioxide into a different more helpful substance. One way is to change carbon dioxide into oxygen, but then you would have way too many carbon molecules. So, my question is what are carbon molecules used for? If we can find out something which a lot of carbon is used, all we need to do is separate the carbon molecule from the two oxygen molecules and then we have a solution.