Colorchanging renewable sponge material captures and stores carbon dioxide

first_imgCarbon dioxide is a growing problem around the world as more of the greenhouse gas enters our atmosphere and slowly aids in the heating of the planet. It is a widely held belief that we need to cut the amount of carbon dioxide entering our atmosphere, with two options available to doing so: produce less of it, or start removing it from the atmosphere ourselves.Cutting carbon dioxide emissions is something moving up the agenda of governments worldwide, but the rate at which change is happening means even the most drastic of actions may come nowhere close to achieving the desired reductions we need to make. So the alternative is to remove and store it instead, a tactic limited only by the amount of people who decide to do take part.As with all technology, if you can make it simple and cheap enough to use, then there’s a greater chance that everyone will take advantage of it. In the case of removing carbon dioxide from the atmosphere, a breakthrough in the Sir Fraser Stoddart laboratory at the Weinberg College of Arts and Sciences, Northwestern University, may be about to offer just such a solution.Carbon dioxide can be removed from the atmosphere by using metal-organic frameworks (MOF) that are generally used to store gases. The problem is, until now suitable MOFs have required the use of harmful solvents and toxic heavy metals meaning they add as much as they take away from the problem.Researchers at the Stoddart laboratory have found a renewable, eco-friendly alternative for creating a MOF. Using nothing but natural ingredients, and relying mainly on a sugar molecule called gamma-cyclodextrin, the MOF relies on the sugar molecules being arranged and held together by metals sourced from potassium benzoate and rubidium hydroxide.The end result is a yellow, sponge-like material that leeches carbon dioxide out of the air and stores it. As more carbon dioxide is captured, the foam turns progressively red. When fully red, the foam is saturated and needs replacing. However, if you then place that foam in an environment away from carbon dioxide, it will naturally escape (known as reversible carbon fixation) and the foam returns to its yellow state again ready to be reused.Such a MOF could be employed in many different locations (roof of your home, roof of your car) for carbon dioxide collection. It’s easy to tell when it has been saturated and can be traded for a new one while the green house gas is stored safely.The fact this material could be used by anyone, relies on a material that can be manufactured in an eco-friendlyt way as well as being reusable, and requires no additional fuel or power to capture carbon dioxide, means it has a lot of potential for future deployment. All it needs is the support of governments and companies willing to handle the saturated MOFs and associated ongoing storage of carbon dioxide.Read more at Science Debate and the Journal of the American Chemical Societylast_img read more