Metal–organic frameworks containing uncoordinated nitrogen: Preparation, modification, and application in adsorption

Significant progress has been made on metal–organic frameworks (MOFs), especially those with functional groups like amines or carboxylic acid groups. MOFs with uncoordinated nitrogen (UCN-MOFs) are attractive for many applications (owing to Lewis basicity and possible coordination) and for possible further modifications to have other functionalities. In this review, recent progress on the preparation, modification for other functionalities, and applications (mainly in adsorption) of UCN-MOFs with or without modification will be discussed. The prospects in the relevant fields are suggested.