Metal-Organic Framework for Emulsifying Carbon Dioxide and Water

Forming emulsions of carbon dioxide (CO2) and water can largely expand the utility of CO2. Herein we propose for the first time the utilization of a metal-organic framework (MOF) for emulsifying CO2 and water. Owing to the hybrid composition, MOF particles can easily assemble at the CO2/water interface to create a rigid protective barrier around the dispersed droplet. The MOF-stabilized CO2 and water emulsion has exceptional stability compared to those emulsions stabilized by surfactants or other solids. Moreover, the CO2 and water emulsion stabilized by MOF is tunable due to the designable features of MOFs and adjustable character of CO2. Such a novel kind of emulsion composed of CO2, water, and MOF provides a facile route for constructing MOF superstructures with many advantages. The macroporous networks and hollow capsules of different kinds of MOFs have been successfully derived from CO2 and water emulsions.