Non-technical summary: Porous materials such as activated charcoal are essential to modern society, with critical applications in energy-efficient chemical separations, pollutant removal for clean water, and as supports for industrial catalysts. Among them, porous organic frameworks, which are carbon-based crystalline materials, stand out for their lightweight nature and precise control over nanometer-sized channels, enabling them to hold or filter molecules of different sizes. However, it remains challenging for existing materials to distinguish between molecules of similar sizes while at the same time capturing many molecules, even though such selectivity and capacity are crucial for many applications. With support from the Solid State and Materials Chemistry program in the Division of Materials Research, this project aims to overcome current limitations by developing a new family of porous organic frameworks that feature both small cavities for selectively recognizing molecules of similar sizes and larger channels for high-capacity uptake and rapid transport. These materials can expand and contract like a sponge, dynamically adjusting their large channels to enhance molecular capture and release, while maintaining the integrity of the small, selective cavities. This adaptive capability could enable more effective technologies for water and air purification, as well as energy-efficient chemical processing. The project contributes to national interests by advancing scientif