title: New High-Pressure Gallium Borate Ga2B3O7(OH) with Photocatalytic Activity.
abstract: The new high-pressure gallium borate Ga2B3O7(OH) was synthesized in a Walker-type multianvil apparatus under high-pressure/high-temperature conditions of 10.5 GPa and 700 °C. For the system Ga-B-O-H, it is only the second known compound next to Ga9B18O33(OH)15·H3B3O6·H3BO3. The crystal structure of Ga2B3O7(OH) was determined by single-crystal X-ray diffraction data collected at room temperature. Ga2B3O7(OH) crystallizes in the orthorhombic space group Cmce (Z = 8) with the lattice parameters a = 1050.7(2) pm, b = 743.6(2) pm, c = 1077.3(2) pm, and V = 0.8417(3) nm(3). Vibrational spectroscopic methods (Raman and IR) were performed to confirm the presence of the hydroxyl group. Furthermore, the band gap of Ga2B3O7(OH) was estimated via quantum-mechanical density functional theory calculations. These results led to the assumption that our gallium borate could be a suitable substance to split water photocatalytically, which was tested experimentally.
authors.affiliation: Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck , Innrain 80-82, A-6020 Innsbruck, Austria.
authors.forename: Daniela
authors.initials: D
authors.lastname: Vitzthum
authors.affiliation: Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck , Innrain 80-82, A-6020 Innsbruck, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Schauperl
authors.affiliation: Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck , Innrain 80-82, A-6020 Innsbruck, Austria.
authors.forename: Christof M
authors.initials: CM
authors.lastname: Strabler
authors.affiliation: Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck , Innrain 80-82, A-6020 Innsbruck, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Brüggeller
authors.affiliation: Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck , Innrain 80-82, A-6020 Innsbruck, Austria.
authors.forename: Klaus R
authors.initials: KR
authors.lastname: Liedl
authors.affiliation: Institute of Pharmacy, Pharmaceutical Technology, University of Innsbruck , Innrain 52c, A-6020 Innsbruck, Austria.
authors.forename: Ulrich J
authors.initials: UJ
authors.lastname: Griesser
authors.affiliation: Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck , Innrain 80-82, A-6020 Innsbruck, Austria.
authors.forename: Hubert
authors.initials: H
authors.lastname: Huppertz