title: Synergistic interaction of Re complex and amine functionalized multiple ligands in metal-organic frameworks for conversion of carbon dioxide.
abstract: A metal-organic framework (MOF) is composed of secondary building units (SBUs) of metal ions and organic ligands to link each SBU. Moreover, the photosynthetic synthesis of a valuable CO chemical from carbon dioxide (CO2) represents an important class of appealing methods. Herein, we find that a molecular photocatalyst with high selectivity and activity can be designed via a fine balance in the proximity of Re complex (ReI(CO)3(BPYDC)(Cl), BPYDC = 2,2'-bipyridine-5,5'-dicarboxylate) and -NH2functionalized multiple ligands composing a MOF photocatalyst, denoted as Re-MOF-NH2. These ligands in Re-MOF-NH2has been confirmed by infrared, UV-visible, and1H nuclear magnetic resonance spectra. Moreover, we show from extended X-ray absorption fine structure and in-situ infrared spectra that the bond corresponding to Re-CO upon introduction of -NH2functional groups is divided into asymmetric bonds of 1.4 Å and 2.3 Å along with different CO2vibrations, thus making the configuration of carbonyl groups in a Re metal complex become asymmetric in addition to aiding formation of CO2intermediates within Re-MOF-NH2. Indeed, both of the uneven electron distribution in asymmetric carbonyl groups for Re-CO and the intermolecular stabilization of carbamate intermediates are proven to give the approximately 3-fold increase in photocatalytic activity for conversion of CO2into CO.
authors.affiliation: Graduate School of Energy, Environmental, Water and Sustainability (EEWS), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.|Department of Chemical and Biological Engineering, Sookmyung Women's University, 100 Cheongpa-ro 47 gil, Yongsan-gu, Seoul, 04310, Republic of Korea.
authors.forename: Un Jin
authors.identifier: http://orcid.org/0000-0002-4854-3587
authors.initials: UJ
authors.lastname: Ryu
authors.affiliation: Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
authors.forename: Sang Jun
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Graduate School of Energy, Environmental, Water and Sustainability (EEWS), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
authors.forename: Hyung-Kyu
authors.initials: HK
authors.lastname: Lim
authors.affiliation: Graduate School of Energy, Environmental, Water and Sustainability (EEWS), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea. linus16@kaist.ac.kr.
authors.forename: Hyungjun
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Chemical and Biological Engineering, Sookmyung Women's University, 100 Cheongpa-ro 47 gil, Yongsan-gu, Seoul, 04310, Republic of Korea. kmchoi@sookmyung.ac.kr.
authors.forename: Kyung Min
authors.initials: KM
authors.lastname: Choi
authors.affiliation: Graduate School of Energy, Environmental, Water and Sustainability (EEWS), Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea. jeung@kaist.ac.kr.|Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea. jeung@kaist.ac.kr.
authors.forename: Jeung Ku
authors.initials: JK
authors.lastname: Kang