title: Efficient Hydrogen Storage and Production Using a Catalyst with an Imidazoline-Based, Proton-Responsive Ligand.
abstract: A series of new imidazoline-based iridium complexes has been developed for hydrogenation of CO2and dehydrogenation of formic acid. One of the proton-responsive complexes bearing two -OH groups at ortho and para positions on a coordinating pyridine ring (3 b) can catalyze efficiently the chemical fixation of CO2and release H2under mild conditions in aqueous media without using organic additives/solvents. Notably, hydrogenation of CO2can be efficiently carried out under CO2and H2at atmospheric pressure in basic water by 3 b, achieving a turnover frequency of 106 h-1and a turnover number of 7280 at 25 °C, which are higher than ever reported. Moreover, highly efficient CO-free hydrogen production from formic acid in aqueous solution employing the same catalyst under mild conditions has been achieved, thus providing a promising potential H2-storage system in water.
authors.affiliation: Research Institute of Energy Frontier, Department of Energy and Environment, National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan.
authors.forename: Lin
authors.identifier: 0000-0001-5644-8865
authors.initials: L
authors.lastname: Wang
authors.affiliation: Research Institute of Energy Frontier, Department of Energy and Environment, National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan.
authors.forename: Naoya
authors.identifier: 0000-0003-4501-1742
authors.initials: N
authors.lastname: Onishi
authors.affiliation: Research Institute of Energy Frontier, Department of Energy and Environment, National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan.
authors.forename: Kazuhisa
authors.identifier: 0000-0002-5857-7668
authors.initials: K
authors.lastname: Murata
authors.affiliation: Graduate School of Science and Engineering, Saitama University, 255 Shimo-ohkubo, Sakura-ku, Saitama, Japan.
authors.forename: Takuji
authors.identifier: 0000-0003-4121-0963
authors.initials: T
authors.lastname: Hirose
authors.affiliation: Chemistry Division, Brookhaven National Laboratory, Upton, NY, 11973-5000, USA.
authors.forename: James T
authors.identifier: 0000-0001-5169-8929
authors.initials: JT
authors.lastname: Muckerman
authors.affiliation: Chemistry Division, Brookhaven National Laboratory, Upton, NY, 11973-5000, USA.
authors.forename: Etsuko
authors.identifier: 0000-0002-0407-6307
authors.initials: E
authors.lastname: Fujita
authors.affiliation: Research Institute of Energy Frontier, Department of Energy and Environment, National Institute of Advanced Industrial Science and Technology, Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan.
authors.forename: Yuichiro
authors.identifier: 0000-0002-9869-5554
authors.initials: Y
authors.lastname: Himeda
mesh_terms: D002384:Catalysis; D005561:Formates / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry*; D048288:Imidazolines / Q000737:chemistry*; D008024:Ligands; D011522:Protons
chemical_list: D005561:Formates; D048288:Imidazolines; D008024:Ligands; D011522:Protons; C030544:formic acid; D006859:Hydrogen
keywords: CO2 hydrogenation; H2 storage; homogeneous catalysis; imidazoline; iridium complex