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Silver-coated poly(methyl acrylic acid) (PSA) core-shell colloid particles were prepared by an in situ chemical reduction method. Crystalline silver/titania composite hollow spheres were obtained by coating the as-prepared PSA/silver particles with an amorphous titania layer and subsequently calcining in Ar atmosphere. SEM and TEM investigation indicated that the size of the as-prepared PSA/silver and PSA/silver/TiO(2) core-shell particles and silver/titania composite hollow particles was fairly uniform and the wall thickness of the hollow spheres was in the range of 40-80 nm. UV-vis absorption spectra were recorded to investigate their optical properties.

Abstract: Flake-like silver nanoparticles have been synthesized in large quantity by simply aging the aqueous solution of silver and urotropine in the presence of poly-(vinylpyrrolidone) (PVP). Silver nanoflakes of different shapes from circular to polygonal could be obtained in different reaction stages. PVP molecules play an important role in the anisotropic growth of silver nanoflakes. The as-synthesized silver colloidal solution remained stable for at least 1 month. Electron diffraction analysis showed that the nanoflakes are well crystallized. The UV-VIS absorption properties have also been studied. [Copyright &y& Elsevier]

Silver nanoshells on styrene–acrylic acid copolymer latex spheres (PSA) were deposited by an in situ chemical reduction method, ageing a colloid solution at 85 °C containing PSA latex, AgNO3, urotropine, and poly-(vinylpyrrolidone). SEM and TEM observations showed that the silver nanoshells were made of closely packed silver nanoparticles of different sizes and morphologies. UV–visible absorption spectra were recorded to investigate their optical properties. [ABSTRACT FROM AUTHOR]

Silver-coated poly(methyl acrylic acid) (PSA) core–shell colloid particles were prepared by an in situ chemical reduction method. Crystalline silver/titania composite hollow spheres were obtained by coating the as-prepared PSA/silver particles with an amorphous titania layer and subsequently calcining in Ar atmosphere. SEM and TEM investigation indicated that the size of the as-prepared PSA/silver and PSA/silver/TiO2 core–shell particles and silver/titania composite hollow particles was fairly uniform and the wall thickness of the hollow spheres was in the range of 40–80 nm. UV–vis absorption spectra were recorded to investigate their optical properties. [Copyright &y& Elsevier]

Abstract: This paper describes a one-pot surfactant-assisted hydrothermal method for the synthesis of Ag-TiO2 composite hollow structures with high photocatalytic activity. TEM measurement reveals that the sample is composed of hollow spheres and their tube-like aggregates. The surfactant cetyltrimethylammonium bromide (CTAB) plays a key role in the construction of the Ag-TiO2 hollow structures. The Ag-TiO2 hollow structures showed effective photocatalytic activity for the decomposition of methyl orange. [Copyright &y& Elsevier]

Abstract: In this paper, we developed a facile low-temperature solution route to prepare radical-shaped ZnO microprisms and to deposit metal silver on the surface of ZnO to form Ag/ZnO microstructures. The samples were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence (PL) spectroscopy. Experimental results show that the deposition of metal Ag nanospecies can be achieved successfully by simply aging the solution at 75°C, and the radical-shaped microstructures of ZnO are well maintained. The Ag/ZnO microstructures exhibit much lower PL emission intensity and much higher photocatalytic activity than those of radical-shaped ZnO microprisms. [Copyright &y& Elsevier]

• Cu 2 O nanospecies anchored on/within mesoporous TiO 2 forming hybrid photocatalyst. • Oxygen vacancy stimulated Z-scheme mechanism inhibits photo corrosion of Cu 2 O. • High activity and stability for hydrogen production in both water and seawater. • Strong coupling between Cu 2 O and TiO 2 extends visible light absorption and charge separation. [Display omitted] Oxygen vacancy stimulated direct Z-scheme Cu 2 O/TiO 2 hybrid photocatalysts were designed and constructed through a Cu2+ ions adsorption-reduction strategy with Cu 2 O nanospecies decorated on/within mesoporous TiO 2 microspheres. Narrow band gap of Cu 2 O favors visible light absorption. The mesoporous structure stabilizes Cu 2 O nanospecies and benefits the efficient charge carrier mobility and light harvest. The high specific surface area provides more photocatalytic active sites for both Cu 2 O and TiO 2 components. Oxygen vacancy stimulated all-solid direct Z-scheme electron transport mechanism was proposed to explain the high activity and stability of the hybrid catalyst. The catalyst behaves enhanced hydrogen evolution rate of 11 mmol h−1 g−1 in water and 5.1 mmol h−1 g−1 in seawater, respectively. The highest AQY of hydrogen production is 15.1% in water (and 8.4% in seawater) at 365 nm. The work will provide new insight for controllable creation of Z-scheme photocatalysts for practical hydrogen evolution from water and seawater splitting. [ABSTRACT FROM AUTHOR]