High-throughput synthesis of zeolitic imidazolate frameworks and application to CO2 capture

A high- throughput protocol was developed for the synthesis of zeolitic imidazolate frameworks ( ZIFs). Twenty- five different ZIF crystals were synthesized from only 9600 microreactions of either zinc( II)/ cobalt( II) and imidazolate/ imidazolate- type linkers. All of the ZIF structures have tetrahedral frameworks: 10 of which have two different links ( heterolinks), 16 of which are previously unobserved compositions and structures, and 5 of which have topologies as yet unobserved in zeolites. Members of a selection of these ZIFs ( termed ZIF- 68, ZIF- 69, and ZIF- 70) have high thermal stability ( up to 390 degrees C) and chemical stability in refluxing organic and aqueous media. Their frameworks have high porosity ( with surface areas up to 1970 square meters per gram), and they exhibit unusual selectivity for CO2 capture from CO2/CO mixtures and extraordinary capacity for storing CO2: 1 liter of ZIF- 69 can hold similar to 83 liters of CO2 at 273 kelvin under ambient pressure.