title: Cooperative insertion of CO2 in diamine-appended metal-organic frameworks.
abstract: The process of carbon capture and sequestration has been proposed as a method of mitigating the build-up of greenhouse gases in the atmosphere. If implemented, the cost of electricity generated by a fossil fuel-burning power plant would rise substantially, owing to the expense of removing CO2 from the effluent stream. There is therefore an urgent need for more efficient gas separation technologies, such as those potentially offered by advanced solid adsorbents. Here we show that diamine-appended metal-organic frameworks can behave as 'phase-change' adsorbents, with unusual step-shaped CO2 adsorption isotherms that shift markedly with temperature. Results from spectroscopic, diffraction and computational studies show that the origin of the sharp adsorption step is an unprecedented cooperative process in which, above a metal-dependent threshold pressure, CO2 molecules insert into metal-amine bonds, inducing a reorganization of the amines into well-ordered chains of ammonium carbamate. As a consequence, large CO2 separation capacities can be achieved with small temperature swings, and regeneration energies appreciably lower than achievable with state-of-the-art aqueous amine solutions become feasible. The results provide a mechanistic framework for designing highly efficient adsorbents for removing CO2 from various gas mixtures, and yield insights into the conservation of Mg(2+) within the ribulose-1,5-bisphosphate carboxylase/oxygenase family of enzymes.
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720, USA.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: McDonald
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720, USA.
authors.forename: Jarad A
authors.initials: JA
authors.lastname: Mason
authors.affiliation: 1] Department of Chemical and Biological Engineering, University of California, Berkeley, California 94720, USA [2] Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
authors.forename: Xueqian
authors.initials: X
authors.lastname: Kong
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720, USA.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Bloch
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720, USA.
authors.forename: David
authors.initials: D
authors.lastname: Gygi
authors.affiliation: Chemistry Department, NIS and INSTM Centre of Reference, University of Turin, Via Quarello 15, I-10135 Torino, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Dani
authors.affiliation: Chemistry Department, NIS and INSTM Centre of Reference, University of Turin, Via Quarello 15, I-10135 Torino, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Crocellà
authors.affiliation: Chemistry Department, NIS and INSTM Centre of Reference, University of Turin, Via Quarello 15, I-10135 Torino, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Giordanino
authors.affiliation: Department of Chemistry, Chemical Theory Center and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Samuel O
authors.initials: SO
authors.lastname: Odoh
authors.affiliation: Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Walter S
authors.initials: WS
authors.lastname: Drisdell
authors.affiliation: Department of Chemical and Biological Engineering, University of California, Berkeley, California 94720, USA.
authors.forename: Bess
authors.initials: B
authors.lastname: Vlaisavljevich
authors.affiliation: Department of Chemistry, Chemical Theory Center and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Allison L
authors.initials: AL
authors.lastname: Dzubak
authors.affiliation: 1] Université Grenoble Alpes, Science et Ingénierie des Matériaux et Procédés (SIMAP), F-38000 Grenoble, France [2] Centre National de la Recherche Scientifique, SIMAP, F-38000, Grenoble, France.
authors.forename: Roberta
authors.initials: R
authors.lastname: Poloni
authors.affiliation: 1] Department of Chemical and Biological Engineering, University of California, Berkeley, California 94720, USA [2] Department of Chemistry, Norwegian University of Science and Technology, Høgskoleringen 5, 7491 Trondheim, Norway.
authors.forename: Sondre K
authors.initials: SK
authors.lastname: Schnell
authors.affiliation: Department of Chemistry, Chemical Theory Center and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Nora
authors.initials: N
authors.lastname: Planas
authors.affiliation: 1] Department of Chemical and Biological Engineering, University of California, Berkeley, California 94720, USA [2] Molecular Foundry, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: Kyuho
authors.initials: K
authors.lastname: Lee
authors.affiliation: Molecular Foundry, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: Tod
authors.initials: T
authors.lastname: Pascal
authors.affiliation: Molecular Foundry, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: Liwen F
authors.initials: LF
authors.lastname: Wan
authors.affiliation: Molecular Foundry, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: David
authors.initials: D
authors.lastname: Prendergast
authors.affiliation: 1] Molecular Foundry, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, USA [2] Department of Physics, University of California, Berkeley, California 94720, USA [3] Kavli Energy Nanosciences Institute, University of California, Berkeley, California 94720, USA.
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Neaton
authors.affiliation: 1] Department of Chemical and Biological Engineering, University of California, Berkeley, California 94720, USA [2] Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA [3] Institut des Sciences et Ingénierie Chimiques, Valais, École Polytechnique Fédérale de Lausanne (EPFL), Rue de l'Industrie 17, CH-1950 Sion, Switzerland.
authors.forename: Berend
authors.initials: B
authors.lastname: Smit
authors.affiliation: Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Kortright
authors.affiliation: Department of Chemistry, Chemical Theory Center and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Gagliardi
authors.affiliation: Chemistry Department, NIS and INSTM Centre of Reference, University of Turin, Via Quarello 15, I-10135 Torino, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Bordiga
authors.affiliation: 1] Department of Chemical and Biological Engineering, University of California, Berkeley, California 94720, USA [2] Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Reimer
authors.affiliation: 1] Department of Chemistry, University of California, Berkeley, California 94720, USA [2] Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Long
mesh_terms: D000327:Adsorption; D000588:Amines / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry* / Q000302:isolation & purification*; D057965:Carbon Sequestration; D017752:Greenhouse Effect / Q000517:prevention & control; D008274:Magnesium / Q000378:metabolism; D012273:Ribulose-Bisphosphate Carboxylase / Q000737:chemistry / Q000378:metabolism; D013696:Temperature; D014961:X-Ray Diffraction
chemical_list: D000588:Amines; D002245:Carbon Dioxide; D012273:Ribulose-Bisphosphate Carboxylase; D008274:Magnesium