In situ Structure Visualization of Direct Air Capture using Metal-Organic Frameworks

Implementation of carbon capture technology such as direct air capture (DAC) is highly needed for EU's climate neutral target. The crystalline porous solids, metal-organic frameworks (MOFs), have demonstrated excel potential for DAC. We recently developed a layered copper-based MOF with a crystal structure that features alternating hydrophobic-hydrophilic channels. Our recent simulations on this MOF indicate a unique channel-selective adsorption mechanism of CO2/H2O, where CO2 molecules occupy the water-free hydrophobic channel at high humidity. To evaluate its potential for DAC, it is highly worthy of carrying out in situ adsorption breakthrough experiment coupled with synchrotron X-ray diffraction to understand the binding behavior of competing components in DAC. This information provides direct visualization of the host-guest interactions, and in combination with complementary density functional theory (DFT) calculation can inform the energy profile of adsorption.