MaLISA - a cooperative method to release adsorbed gases from metal-organic frameworks

Abstract

Metal organic frameworks (MOFs) have emerged as ideal adsorbents for carbon capture owing to their exceptionally high surface areas and chemical versatility. However, the significant energy penalty for the regeneration of MOF adsorbents is one of the biggest barriers to their widespread deployment. To overcome this challenge, there has been a recent surge of high quality research to adapt MOFs to be responsive to external stimuli including light and magnetic fields such that they might expel adsorbed molecules at low energy cost and high efficiency. To further minimize the energy cost required for the regeneration of MOF adsorbents, we present a robust dual stimuli-responsive MOF, magnetic PCN-250 (mPCN), which shows strong responses to both magnetic induction and UV light following two distinct working mechanisms, magnetic induced localised heat and light induced localised bending of the MOF organic linkers. Both responses are able to collaboratively trigger a record high gas desorption (up to 96.8% of CO2 desorption at 1 bar) from mPCN through a MaLISA process, confirming a potentially low-energy yet highly efficient strategy to regenerate MOF adsorbents on a large scale. This is the 1st exploration in the use of multiple stimuli to improve gas liberation from MOF adsorbents.