Crystalline porous material based membranes for hydrogen separation

In recent years, hydrogen has gained significant recognition as a "green energy" source. However, the current dominant method of hydrogen production through fossil energy reforming inevitably introduces impurities, which hinders the practical application of produced hydrogen. Therefore, hydrogen purification technology plays a crucial role in connecting the upstream and downstream of hydrogen energy. Among various purification technologies, membrane separation stands out due to its high efficiency, simplicity, and low energy consumption. Crystalline porous materials (CPMs) with uniform and regular pore structures show great promise in membrane technology for separation applications. Two types of membranes, crystalline porous membranes (CPMBs) and mixed-matrix membranes (MMMs), are particularly noteworthy. This review explores the potential of CPMs as powerful and disruptive separation membranes for efficient hydrogen purification. It covers various aspects ranging from the design of microscopic pore structures, interface optimization, and membrane preparation methods, to the performance of hydrogen separation. The precise design of pore structures can effectively address the challenge of balancing permeability and selectivity of resultant membranes. Through interfacial optimization and scalable processing approaches, the development of high-performance hydrogen separation membranes becomes feasible. Finally, the review summarizes the challenges associated with CPM-based hydrogen separation membranes and provides an outlook on prospective research directions.