title: Photocatalyzed Hydrogen Evolution from Water by a Composite Catalyst of NH2-MIL-125(Ti) and Surface Nickel(II) Species.
abstract: A composite of the metal-organic framework (MOF) NH2-MIL-125(Ti) and molecular and ionic nickel(II) species, catalyzed hydrogen evolution from water under UV light. In 95 v/v % aqueous conditions the composite produced hydrogen in quantities two orders of magnitude higher than that of the virgin framework and an order of magnitude greater than that of the molecular catalyst. In a 2 v/v % water and acetonitrile mixture, the composite demonstrated a TOF of 28 mol H2g(Ni)-1h-1and remained active for up to 50 h, sustaining catalysis for three times longer and yielding 20-fold the amount of hydrogen. Appraisal of physical mixtures of the MOF and each of the nickel species under identical photocatalytic conditions suggest that similar surface localized light sensitization and proton reduction processes operate in the composite catalyst. Both nickel species contribute to catalytic conversion, although different activation behaviors are observed.
authors.affiliation: Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zürich, Wolfgang-Pauli-Str. 10, 8093, Zürich, Switzerland.
authors.forename: Kim
authors.identifier: http://orcid.org/0000-0003-0838-0864
authors.initials: K
authors.lastname: Meyer
authors.affiliation: SABIC, P.O. Box 4545-4700, 23955, Thuwal, Saudi Arabia.
authors.forename: Shahid
authors.identifier: http://orcid.org/0000-0002-3710-3068
authors.initials: S
authors.lastname: Bashir
authors.affiliation: Institute of Energy Technologies, and Centre for Research in NanoEngineering, Technical University of Catalonia, Avda. Diagonal 647, 08028, Barcelona, Spain.
authors.forename: Jordi
authors.identifier: http://orcid.org/0000-0002-7447-9582
authors.initials: J
authors.lastname: Llorca
authors.affiliation: SABIC, P.O. Box 4545-4700, 23955, Thuwal, Saudi Arabia. IdrissH@SABIC.com.
authors.forename: Hicham
authors.identifier: http://orcid.org/0000-0001-5198-9232
authors.initials: H
authors.lastname: Idriss
authors.affiliation: Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institute, 5232, Villigen, Switzerland. marco.ranocchiari@psi.ch.
authors.forename: Marco
authors.identifier: http://orcid.org/0000-0002-4460-8742
authors.initials: M
authors.lastname: Ranocchiari
authors.affiliation: Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zürich, Wolfgang-Pauli-Str. 10, 8093, Zürich, Switzerland. jeroen.vanbokhoven@chem.ethz.ch.|Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institute, 5232, Villigen, Switzerland. jeroen.vanbokhoven@chem.ethz.ch.
authors.forename: Jeroen A
authors.identifier: http://orcid.org/0000-0002-4166-2284
authors.initials: JA
authors.lastname: van Bokhoven
keywords: hydrogen; metal-organic frameworks; nickel; photocatalysis