Supercritical fluid processing for metal-organic frameworks, porous coordination polymers, and covalent organic frameworks

The synthesis and processing of porous materials is a particularly fertile area for supercritical fluid (SCF) technology. Well-designed metal-organic hybrid porous materials such as metal-organic frameworks (MOFs) and porous coordination polymers (PCPs), which are constructed from metal-containing nodes and organic linkers, have recently been recognized as an intriguing class of crystalline nanoporous materials with a wide variety of potential applications in areas including gas storage, compound separation, biomedicine, chemical sensing, and catalysis. Furthermore, covalent organic frameworks (COFs) constructed from light elements have been developed. Recent research in the rapidly expanding field of MOFs, PCPs and COFs has demonstrated that SCF technologies, such as drying, impregnation, and synthesis, are effective approaches for processing and improving MOFs, PCPs and COFs. This short review describes the processing of MOFs, PCPs and COFs using supercritical CO2 and its mixtures. Selected examples are presented, and current achievements and challenges are summarized.