Susumu Kitagawa developed, from the early 1990s, porous coordination polymers with permanent pores capable of adsorbing and releasing gas molecules in a controlled way — the so-called metal-organic frameworks (MOFs). These crystalline materials present internal surfaces of up to thousands of square meters per gram, allowing them to capture CO2, store hydrogen, desalinate water, or release drugs in a targeted way. Richard Robson in Australia and Omar Yaghi in the US worked in parallel on analogous materials. Kitagawa, Robson, and Yaghi shared the Nobel Prize in Chemistry in 2025.