Revisiting Pressure-Induced Transitions in Mesoporous Anatase TiO₂

Abstract

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Sub-THz Vibrational Dynamics in Ordered Mesoporous Silica Nanoparticles

“…We did not observe peaks in the optical phonon range for the MSNs using Brillouin or low-frequency Raman scattering. However, as discussed in the Introduction, peaks at larger frequencies (>300 GHz) were reported in a previous work for mesoporous titania [9]. To attempt a qualitative comparison, we performed the phonon bands' calculations using an isotropic approximation of anatase TiO 2 (c L = 8326 and c T = 3863 m/s) and the porosity and pore diameter reported in that study, assuming the same 2D hexagonal mesoporous lattice structure.…”

“…However, to the best of our knowledge, the periodicity of the mesoporous structure has never been explicitly taken into account. In a recent work [ 9 ], some of us investigated mesoporous titania using Raman scattering including in the low-wavenumber range down to ( 300 GHz). Two peaks were observed in the sub-THz range ( and THz).…”

Utilizing the Built‐in Electric Field of p–n Junctions to Spatially Propel the Stepwise Polysulfide Conversion in Lithium–Sulfur Batteries

“…The Raman spectrum of p‐Co 3 O 4 /n‐TiO 2 ‐HPs is similar to that of pure p‐Co 3 O 4 ‐HPs in the presence of the F 2g , E g , and A 1g modes, [ 9 ] whereas no TiO 2 related features are observed. [ 10 ] Notably, by regulating the Co/Ti feed ratio from 5:1 to 1:1, the obtained annealed products demonstrate the characteristic diffraction peaks of Co 3 O 4 (Figures S7 and S8, Supporting Information). Aggregations are obtained instead of Co/Ti LDHs by further decreasing the Co/Ti feed ratio to 1:1 (Figure S7, Supporting Information).…”

Pressure Behavior of the Zero Thermal Expansion Material Sc1.5Al0.5W3O12

“…High pressure (HP) Raman spectroscopy experiments were carried out using a homemade spectrometer in backscattering geometry. 33 The laser wavelength was 532 nm, and the laser power was adjusted in order to avoid heating effects on the samples and to improve the signal-to-noise ratio. The laser beam was focused with a 50× objective lens, and the signal was dispersed by a grating of 1800 grooves/mm.…”