Tailoring the crystal growth of quartz on silicon for patterning epitaxial piezoelectric films.

Epitaxial films of piezoelectric α-quartz could enable the fabrication of sensors with unprecedented sensitivity for prospective applications in electronics, biology and medicine. However, the prerequisites are harnessing the crystallization of epitaxial α-quartz and tailoring suitable film microstructures for nanostructuration. Here, we bring new insights into the crystallization of epitaxial α-quartz films on silicon (100) from the devitrification of porous silica and the control of the film microstructures: we show that by increasing the quantity of devitrifying agent (Sr) it is possible to switch from an α-quartz microstructure consisting of a porous flat film to one dominated by larger, fully dense α-quartz crystals.

Fabrication of α-Fe2O3/In2O3 composite hollow microspheres: A novel hybrid photocatalyst for toluene degradation under visible light.

The α-Fe2O3/In2O3 composite hollow microspheres were first synthesized through a well-designed two-step hydrothermal approach with an aim to promote the photocatalytic activity of the pure In2O3. The morphologies, phase structures, and optical properties of the resultant samples were systematically characterized by field-emission scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, UV-vis diffuse-reflectance, and photoluminescence spectroscopy. The α-Fe2O3 nanoparticles acted as visible-light sensitizer, which were well-decorated on the surface of the In2O3 hollow microspheres.