28th Annual Stauffer Lectureship (Day 1 of 2): Professor Jeffrey R. Long, UC Berkeley
Photo Credit: Alain Kesseru
About the Seminar
Cooperative Adsorption and Gas Separations in Metal–Organic Frameworks
The tunability of metal–organic frameworks offers the possibility of designing powerful new adsorbents that selectively adsorb and release gas molecules in a cooperative manner. An initial example of such a material was realized in mmen-Mg2(dobpdc), which exhibits step-shaped CO2 adsorption isotherms arising from a cooperative insertion mechanism that leads to ammonium carbamate chains running along the pore surface. This mechanism has now been widely elaborated, leading to diamine-appended adsorbents that cycle at high capacity in the presence of water, and are capable of efficiently separating CO2 from flue gas emissions, air, natural gas, and biogas. Stabilization of the materials through functionalization with appropriately structured tetraamines further enables cooperative CO2 capture at high temperatures, as well as regeneration via steam stripping. This type of cooperative mechanism has been extended to the selective adsorption of CS2, and a related mechanism has been shown to be operational in alcoholamine-appended frameworks. In addition, efforts to expand the scope of cooperative adsorption have led to new metal-organic frameworks containing: (i) chains of high-spin iron(II) sites that can cooperatively adsorb CO via a spin transition mechanism, (ii) chains of redox-active cobalt(II) sites that exhibit negative cooperativity upon uptake of O2, and (iii) binuclear metal complexes that enable the cooperative adsorption of NH3 through a ligand insertion mechanism. Finally, the first porous materials that can effectively capture gases such as CO2 at elevated temperatures in the range 200-300 °C will be introduced.
About the Speaker
Jeffrey R. Long is the C. Judson King Distinguished Professor of Chemistry and Chemical & Biomolecular Engineering and Director of the Institute for Decarbonization Materials at the University of California, Berkeley, and is a Faculty Senior Scientist in the Materials Sciences Division at Lawrence Berkeley National Laboratory. He served as Chair of the Division of Inorganic Chemistry of the American Chemical Society in 2012 and as a founding Associate Editor of the journal Chemical Science. He co-founded two companies: Mosaic Materials, which was acquired by Baker Hughes in 2022 and is developing metal–organic frameworks for low-energy carbon dioxide capture, and ChemFinity Technologies, which is producing materials for the selective removal of toxic and high-value ions from water. His 395 publications have received more than 97,000 citations, and his recent awards include the Eni Award Energy Transition Prize, election to the National Academy of Sciences, the Royal Society of Chemistry Ludwig Mond Award, the American Chemical Society F. Albert Cotton Award in Synthetic Inorganic Chemistry, and election to the American Academy of Arts and Sciences.