title: Reversible hydrogen storage using CO2 and a proton-switchable iridium catalyst in aqueous media under mild temperatures and pressures.
abstract: Green plants convert CO(2) to sugar for energy storage via photosynthesis. We report a novel catalyst that uses CO(2) and hydrogen to store energy in formic acid. Using a homogeneous iridium catalyst with a proton-responsive ligand, we show the first reversible and recyclable hydrogen storage system that operates under mild conditions using CO(2), formate and formic acid. This system is energy-efficient and green because it operates near ambient conditions, uses water as a solvent, produces high-pressure CO-free hydrogen, and uses pH to control hydrogen production or consumption. The extraordinary and switchable catalytic activity is attributed to the multifunctional ligand, which acts as a proton-relay and strong π-donor, and is rationalized by theoretical and experimental studies.
authors.affiliation: Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, USA. hull@bnl.gov
authors.forename: Jonathan F
authors.initials: JF
authors.lastname: Hull
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Himeda
authors.forename: Wan-Hui
authors.initials: WH
authors.lastname: Wang
authors.forename: Brian
authors.initials: B
authors.lastname: Hashiguchi
authors.forename: Roy
authors.initials: R
authors.lastname: Periana
authors.forename: David J
authors.initials: DJ
authors.lastname: Szalda
authors.forename: James T
authors.initials: JT
authors.lastname: Muckerman
authors.forename: Etsuko
authors.initials: E
authors.lastname: Fujita
mesh_terms: D002245:Carbon Dioxide; D002384:Catalysis; D004736:Energy-Generating Resources; D006859:Hydrogen; D007495:Iridium; D011312:Pressure; D013696:Temperature; D014867:Water
chemical_list: D014867:Water; D002245:Carbon Dioxide; D007495:Iridium; D006859:Hydrogen