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As a kind of rare materials, nano-silver has broad application prospects in the fields of catalysis, medical treatment, new energy and so on. However, there are few reports on the systematic research of nano-silver in ceramic glazes. In this work, different color ceramic glazes were produced by tuning the nano-silver content and optimizing the firing process. The crystalline phase composition, micro-morphology and elemental distribution of fired glazes were analyzed and discussed in depth. The elemental composition and distribution of the samples were studied. The surface of the glazes with varying Ag contents fired under the reducing atmosphere exhibited blue-white. And the blue color is attributable to Rayleigh scattering that may arise because the phase-separation structures existed in glazes. Interestingly, the color of the ceramic glazes with varying Ag contents changed to golden-yellow when the ceramic glazes were fired under the air atmosphere. Golden-yellow color of the samples fired under the air atmosphere is mainly attributable to the silver nano-particles, though Ag+ may be existed in the glazes.

In this work, heterostructured Au@PbTiO3 nanoplates were synthesized successfully via a simple hydrothermal process. It is revealed that Au islands with the size of 8–20 nm selectively deposited on the positively polarized surface of the single-crystal and single-domain PbTiO3 nonaplates. The composite demonstrates an efficient photocatalytic performance toward degradation of Rhodamine B (RhB) solution under UV light. The possible mechanism is that the ferroelectric polarization efficiently separates the photogenerated electrons and holes and reduces the recombination of them. Then, the ferroelectric polarization field urged the electrons concentrated on the positively polarized surface and then transformed oxygen into superoxide radicals to enhance the photocatalytic activity. Recycled activity tests show that the heterostructured Au@PbTiO3 nanoplates would inhibit the photocorrosion behavior and provide high stability.

By using a novel Zn(S) 2 L complex (L = N–hexyl–3–{2–(4–(2,2′:6′,2′′–terpyridin–4′–yl)phenyl)ethenyl}carbazole) as a surface stabilizing agent, the self–assembled microspheres of Zn(S) 2 L–capped ZnS nanocrystals are obtained in a simple ethanol solvothermal process. Because of the strong π character of the two terminal sulfur atoms (S 1– valence state) in the Zn(S) 2 L complex, the Zn(S) 2 L complex could incorporate ZnS nanocrystals together by a homologous Zn⟵S→Zn unit interface. In the work, the homologous Zn⟵S→Zn unit interface is proposed to function as a π–conjugated bridge for effective electron–transfer transition from Zn(S) 2 L moiety to ZnS nanocrystal to significantly improve the photoelectric response performance, such as the long lifetime of photogenerated charge carriers from 8 × 10 −8 s to 4 × 10 −5 s and the high recombination luminescence quantum efficiency (QE) up to 69%, which are confirmed by the systematically investigation with Raman spectra, XPS spectra, Uv–vis absorption spectra, photoluminescence (PL) spectra and transient photovoltage (TPV) technique. The ZnS/Zn(S) 2 L used as extra electron donor in organic/inorganic hybrid solar cell device could increase performance up to about 30%.

Fe3O4@SiO2-SO3H nanocomposites were successfully synthesised as the efficient magnetically separable solid acid catalysts for an esterification reaction. The resultant catalysts were characterised by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, vibrating sample magnetometer (VSM), and nitrogen physical adsorption analyses [Brunauer–Emmett–Teller (BET) theory]. The catalytic activities of as-prepared Fe3O4@SiO2-SO3H nanocomposites were also investigated for the esterification of n-butyl acetate and isoamyl acetate. The acid esterification rate was confirmed by gas chromatography. The results showed that the Fe3O4@SiO2-SO3H nanocomposites can be as candidate cataysts for the concentrated H2SO4 for the esterification reaction of n-butyl alcohol or isoamyl alcohol. More importantly, the magnetic catalysts can be easily separated from the reaction system by a magnetic bar and reused at least three recycles without significant degradation of their activities.

This is the first time a series of chemically homogeneous superlattice Cu7.2Sx (x = 4.07, 4.52, 6.01, 6.20, 6.45) nanowires have been successfully synthesized by heavy doping of S2 species in Cu7.2S4 lattice through a simple wet-chemical route. This superlattice structure is a polytypoid structure tuned by adjusting the atom ratio of S2 to S in lattice configuration. The perfect superlattice Cu7.2S6.20 structure interestingly consists of two alternating lattice fringes corresponding to the atom layers of Cu–S and Cu–S2 in an even spacing of 5.70 A. The article describes the formation, morphology, composition and structure of the Cu7.2Sx superlattice nanowires. Photoluminescence (PL) spectra and transient photovoltage (TPV) measurements reveal that the generation and separation efficiency of the photogenerated charges of Cu7.2Sx nanowires could be greatly improved by adjusting the S2/S ratio in the lattice configuration, and thus enhance the luminescence quantum efficiency. This study reveals that the S2 species in Cu7.2Sx nanowires play a very important role in determining the dynamic properties of photogenerated charge carriers.

The phase and morphology evolution in the Bi–W–Cl–O solvothermal system was investigated. The products were characterised by X-ray diffraction, SEM and high resolution TEM. The optical properties and photocatalytic performance of the samples were evaluated. The results show that the composite Bi2WO6/BiOCl sample was obtained for the reaction time of 15 h. The light absorption ability and the photodegradation efficiency were enhanced obviously for Bi2WO6/BiOCl. The mechanisms for the formation of the composite and the optimisation of the photocatalytic activity were also discussed.

In this study, we present flower-like rutile TiO 2 superstructures could be successfully fabricated by taking advantage of a facile solution-phase approach at room temperature. The surface area and amount of surface hydroxyl groups on rutile TiO 2 superstructures could be tuned by calcing the sample at different temperatures. Photocatalytic experiments demonstrated the room temperature synthesized rutile TiO 2 superstructures exhibited excellent photocatalytic activity compared to that of the calcined ones, which were thought to be mainly attributed to its large surface area. We further studied the photocatalytic process of RhB on different rutile TiO 2 superstructures by active species trapping experiments and analyzed the relationship between the major active species and the main influencing factors responsible for the photocatalytic performance for elucidating a surface area and surface charge cooperative photocatalytic mechanism.

Ag3PO4/BiOBr composites were prepared by a facile room temperature liquid phase method. The samples were characterised by X-ray diffraction, SEM, energy dispersive X-ray spectroscopy, ultraviolet–visible and photoluminescence (PL) techniques. The photocatalytic activity was evaluated by photodegrading methylene blue under visible light irradiation. The results show that Ag3PO4/BiOBr composites were successfully formed and the Ag3PO4 nanoparticles were randomly distributed on the surface of BiOBr nanosheets. The composites exhibit better visible light absorption ability, and the PL results show that the composites have enhanced photogenerated carrier separation efficiency. The best photocatalytic performance is obtained for the sample with Ag/Bi ratio of 0·5, the photocatalytic efficiency of which is six times that of BiOBr. The improvement of the photocatalytic activity is associated with the coupling effects of the two semiconductors.

Copper selenide films with different phase and morphology were synthesized on copper substrate through controlling reaction solvent by microwave-assisted nonaqueous approach. The films were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The result showed that the pure films could be obtained using cyclohexyl alcohol or benzyl alcohol as solvent. The cubic Cu 2− x Se dendrites were synthesized in cyclohexyl alcohol reaction system and hexagonal CuSe flaky crystals were obtained with benzyl alcohol as solvent.

A new series of ternary semiconductor compounds, Cu7.2(SexS1−x)4 (0.2 ≤ x ≤ 0.8) nanocrystallites, that exhibited good photocatalytic activity under visible-light irradiation, were facilely synthesized under mild conditions. The Cu7.2(SexS1−x)4 nanocrystallites were characterized by powder X-ray diffraction, transmission electron microscopy, energy dispersive X-ray spectroscopy and UV-Vis absorption spectra. From X-ray data it is found that the cell constant a of different samples varies linearly with the composition x as: a (A) = 5.5959 + 0.1586x. UV-Vis absorption spectra indicate that the apparent band gap energies can be tuned by adjusting the composition x so as to better match to the whole solar spectrum. Unlike the most studied TiO2 that only responds to the UV-light irradiation, the present Cu7.2(SexS1−x)4 nanocrystallites exhibited much better photocatalytic activity under visible light on degradation of RhB. It is believed that the photocatalytic superiority of the Cu7.2(SexS1−x)4 nanocrystallites is mainly due to the compositional gradient arisen from uneven distribution of Se/S compositions in the compounds, which may induce a more efficient charge separation/transport in the Cu7.2(SexS1−x)4 photocatalysts.

Even though dye degradation is a successful application of semiconductor photocatalysis, the roles of reactive species in dye degradation have not received adequate attention. In this study, we systematically investigated the degradation of two cationic dyes (rhodamine B and methylene blue) and two anionic dyes (methyl orange and orange G) over negatively surface-charged In2S3 nanoflowers synthesized at 80 °C under indoor daylight lamp irradiation. It is notable to find In2S3 nanoflowers were more stable in anionic dyes degradation compared to that in cationic dyes removal. The active species trapping experiments indicated photogenerated electrons were mainly responsible for cationic dyes degradation, but holes were more important in anionic dyes degradation. A surface-charge-dependent role of reactive species in ionic dye degradation was proposed for revealing such interesting phenomenon. This study would provide a new insight for preparing highly efficient daylight-driven photocatalyst for ionic dyes degradation.