title: New hydrogen-evolution heteronanostructured photocatalysts: Pt-Nb3 O7 (OH) and Cu-Nb3 O7 (OH).
abstract: Nanorods of triniobium hydroxide heptaoxide, Nb3 O7 (OH), were synthesized by means of a hydrothermal method. Subsequently, Pt and CuO nanoparticles were introduced on the surface of Nb3 O7 (OH) nanorods by a microwave-assisted solvothermal nucleation and growth technique. The resulting Pt- and CuO-decorated Nb3 O7 (OH) nanorods demonstrated uniform particle dispersion and were fully characterized by X-ray diffraction, electron microscopy, and spectroscopic analysis. Furthermore, the solar-powered photocatalytic hydrogen production properties of these heteronanostructures were studied. The solar-driven H2 formation rate over Pt-Nb3 O7 (OH) was determined to be 710.4 ± 1.7 μmol g(-1) h(-1) with a quantum efficiency of ϕ=5.40% at λ=380 nm. Interestingly, the as-prepared CuO-Nb3 O7 (OH) heteronanostructure was found to be inactive under solar irradiation during an induction phase, whereupon it undergoes an in situ photoreduction process to form the photocatalytically active Cu-Nb3 O7 (OH). This restructuring process was monitored by an in situ measurement of the time-evolution of the optical absorption spectra. The solar-powered H2 production for the restructured compound was determined to be 290.3 ± 5.1 μmol g(-1) h(-1) .
authors.affiliation: Materials Chemistry Research Group, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6 (Canada); Department of Chemistry, American University of Beirut, Beirut 11-0236 (Lebanon).
authors.forename: Mohamad
authors.initials: M
authors.lastname: Hmadeh
authors.forename: Veronika
authors.initials: V
authors.lastname: Hoepfner
authors.forename: Eduardo
authors.initials: E
authors.lastname: Larios
authors.forename: Kristine
authors.initials: K
authors.lastname: Liao
authors.forename: Jia
authors.initials: J
authors.lastname: Jia
authors.forename: Miguel
authors.initials: M
authors.lastname: Jose-Yacaman
authors.forename: Geoffrey A
authors.initials: GA
authors.lastname: Ozin
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry*; D043942:Nanotubes / Q000737:chemistry*; D009556:Niobium / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D055668:Photochemical Processes; D017671:Platinum Compounds / Q000737:chemistry*
chemical_list: D010087:Oxides; D017671:Platinum Compounds; D009556:Niobium; D003300:Copper; D006859:Hydrogen
keywords: heteronanostructure; hydrogen production; photocatalysis; triniobium hydroxide heptaoxide