title: Experimental and theoretical investigation of a mesoporous K(x)WO3 material having superior mechanical strength.
abstract: Mesoporous materials with tailored properties hold great promise for energy harvesting and industrial applications. We have synthesized a novel tungsten bronze mesoporous material (K(x)WO3; x ∼ 0.07) having inverse FDU-12 type pore symmetry and a crystalline framework. In situ small angle X-ray scattering (SAXS) measurements of the mesoporous K(0.07)WO3 show persistence of a highly ordered meso-scale pore structure to high pressure conditions (∼18.5 GPa) and a material with remarkable mechanical strength despite having ∼35% porosity. Pressure dependent in situ SAXS measurements reveal a bulk modulus κ = 44 ± 4 GPa for the mesoporous K(x)WO3 which is comparable to the corresponding value for the bulk monoclinic WO3 (γ-WO3). Evidence from middle angle (MAXS) and wide angle X-ray scattering (WAXS), high-resolution transmission electron microscopy (HR-TEM) and Raman spectroscopy shows that the presence of potassium leads to the formation of a K-bearing orthorhombic tungsten bronze (OTB) phase within a monoclinic WO3 host structure. Our ab initio molecular dynamics calculations show that the formation of the OTB phase provides superior strength to the mesoporous K(0.07)WO3.
authors.affiliation: Department of Physics, Astronomy & Materials Science, Missouri State University, Springfield, MO 65897, USA. sdey@sunypoly.edu.
authors.forename: Sonal
authors.initials: S
authors.lastname: Dey
authors.affiliation: Department of Physics, Astronomy & Materials Science, Missouri State University, Springfield, MO 65897, USA. sdey@sunypoly.edu.
authors.forename: Sean T
authors.initials: ST
authors.lastname: Anderson
authors.affiliation: Department of Physics, Astronomy & Materials Science, Missouri State University, Springfield, MO 65897, USA. sdey@sunypoly.edu.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Mayanovic
authors.affiliation: Department of Physics, Astronomy & Materials Science, Missouri State University, Springfield, MO 65897, USA. sdey@sunypoly.edu.
authors.forename: Ridwan
authors.initials: R
authors.lastname: Sakidja
authors.affiliation: Department of Chemistry, Lehigh University, Bethlehem, PA 18015, USA.
authors.forename: Kai
authors.initials: K
authors.lastname: Landskron
authors.affiliation: Department of Chemistry, Lehigh University, Bethlehem, PA 18015, USA.
authors.forename: Berenika
authors.initials: B
authors.lastname: Kokoszka
authors.affiliation: Department of Chemistry, Lehigh University, Bethlehem, PA 18015, USA.
authors.forename: Manik
authors.initials: M
authors.lastname: Mandal
authors.affiliation: Cornell High Energy Synchrotron Source, Wilson Laboratory, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Zhongwu
authors.initials: Z
authors.lastname: Wang
mesh_terms: D046529:Microscopy, Electron, Transmission; D056004:Molecular Dynamics Simulation; D049329:Nanostructures / Q000737:chemistry / Q000648:ultrastructure; D010087:Oxides / Q000737:chemistry*; D016062:Porosity; D053838:Scattering, Small Angle; D013059:Spectrum Analysis, Raman; D014414:Tungsten / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D010087:Oxides; C511604:tungsten oxide; D014414:Tungsten