The status and prospects of materials for carbon capture technologies

In order to combat climate change, carbon dioxide (CO₂) emissions from industry, transportation, buildings, and other sources need to be captured and long-term stored. Decarbonization of these sources requires special types of materials that have high affinities for CO₂. Potassium hydroxide is a benchmark aqueous sorbent that reacts with CO₂ to convert it into K₂CO₃ and subsequently precipitated as CaCO₃. Another class of carbon capture materials is solid sorbents that are usually functionalized with amines or have natural affinities for CO₂. The next wave of materials for carbon capture under investigation includes activated carbon, metal–organic frameworks, zeolites, carbon nanotubes, and ionic liquids. In this issue of MRS Bulletin, some of these materials are highlighted, including solvents and sorbents, membranes, ionic liquids, and hydrides. Other materials that can capture CO₂ from low concentrations of gas streams, such as air (direct air capture) are also discussed. Also covered in this issue are machine learning-based computer algorithms developed with the goal to speed up the progress of carbon capture materials development, and to design advanced materials with high CO₂ capacity, improved capture and release kinetics, and improved cyclic durability. Graphical abstract: [Figure not available: see fulltext.]