There are a number of interesting efforts being undertaken in order to make the CO2 capture from the power plant flue gas more effective and less costly. The use of plastic membranes for the CO2 separation and capture is one of the newest I came across.

A polypropylene membrane carbon dioxide separation system has been developed by the University of Melbourne, Australia, which could be used in power plants, according to an article published in Australian business / environmental magazine ECOS. Teflon membranes have already been used in pilot carbon capture systems, but polypropylene is much cheaper.

It is not clear to what extent this will decrease the costs, but I reckon that membrane costs are one of the more significant costs in CO2 capture, so this is indeed good news.

Do you know of any other cheap material such as this which is intended to be used in CO2 capture?

Here is a link that might be useful: CO2 Separation and Capture