Novel heterostructured CdS/BiVO4 nanocomposites were fabricated in a low-temperature water bath system. The uniform CdS nanoparticles with an average size of 20 nm were homogeneously interspersed on BiVO4 nanosheets. The coupling of BiVO4 and CdS nanoparticles could notably promote the photocatalytic activity. The composites reached a high H2-production rate of 0.57 mmol h–1 under visible light irradiation, about 5.18 times higher than that of pure CdS nanoparticles. The dominant active species in the photocatalytic system were also confirmed by the radical trapping test. Based on the calculation and experimental results, a Z-scheme photocatalytic mechanism was proposed, which was further confirmed by the electrochemical impedance spectroscopy and the cycling test. The Z-scheme photocatalytic system endows the CdS/BiVO4 heterostructure with strong reducibility and oxidizability and excellent stability.Keywords: CdS/BiVO4; Heterostructure; Hydrogen evolution; Photocatalystic;

Novel CdS–rGO nanocomposites were fabricated by wrapping CdS particles with reduced graphene oxide sheets through a facile mixing process with ethylene glycol as solvent. The photocatalytic behavior of the CdS–rGO nanocomposites was evaluated by the photocatalytic degradation of Congo red under simulated sunlight irradiation. Compared with the bare CdS, the photocatalytic activity and stability of the composites were much enhanced, resulting from the involving of the rGO sheets as chainmail, which facilitates the charge separation, suppresses the recombination of electron–hole pairs, and improves light conversion efficiency of catalysts. The radical trapping test results suggest that the ∙O2− and/or ∙OH radicals are the dominant active oxygen species in the CdS–rGO photocatalytic process. And a possible photocatalytic mechanism was proposed.

•Facile ultrasound-assisted ion exchange method was developed for the fabrication of CdS/Ag2S thin films.•Hybrid solar cells were constructed with FTO/CdS/Ag2S/P3HT/Au.•The solar cell displays relatively higher power conversion efficiency than that of FTO/CdS/P3HT/Au.A facile ultrasound-assisted ion exchange route was developed for the synthesis of CdS/Ag2S heterojunctions by ion exchange between the nanostructured CdS film and [Ag(NH3)2]+ under ultrasonication. The CdS/Ag2S heterojunction film was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-vis DRS spectroscopy, photoelectrochemical measurements, and the transient photovoltage (TPV) technique. CdSAg2S heterojunctions exhibit a dense morphology, enhanced visible light absorption and stronger photocurrent response than the pure CdS films. Poly(3-hexylthiophene) (P3HT) was then spin coated into the CdS/Ag2S framework. Hybrid solar cells constructed with FTO/CdS/Ag2S/P3HT/Au display relatively higher power conversion efficiency than FTO/CdS/P3HT/Au.A facile ultrasound-assisted ion exchange route was developed for the synthesis of CdS/Ag2S heterojunctions by ion exchange between the CdS nanostructured film and [Ag(NH3)2]+ under ultrasonication. Hybrid solar cells constructed with FTO/CdS/Ag2S/P3HT/Au display relatively higher power conversion efficiency than FTO/CdS/P3HT/Au.

Uniform CeO2 nanoparticles and nanorods were selectively synthesized through a hydrothermal method, which was followed by calcination. UV-vis diffuse reflection spectra (DRS) exhibited that the obtained powders were responsive to visible light, which might be attributed to the presence of increased oxygen vacancies in the ceria structure. The enhanced photocatalytic activities of the CeO2 nanostructures were comparatively evaluated by the photodegradation of rhodamine B under visible light, which far exceeded those of commercial P25 powders. The mechanism was investigated through carrier trapping experiments. Moreover, a glass carbon electrode (GCE) decorated with the resulting nanocrystals was used to examine their electrocatalytic behavior for p-nitrophenol degradation in a basic solution. The results demonstrated substantially that the obtained CeO2 nanoparticles possess excellent photocatalytic and electrocatalytic activities.

Uniform LnFeO3 (Ln=Pr, Y) nano-/submicro-particles were prepared by a sol–gel method with the assistance of glycol at 800 °C for 4 h. The as-synthesized LnFeO3 was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–vis diffuse reflectance spectra. The photocatalytic behaviors of LnFeO3 nanoparticles were evaluated by the photodegradation of rhodamine-B under visible light irradiation. The results indicate that the as-prepared PrFeO3 nanoparticles exhibit remarkable visible-light photocatalytic activity through the synergism of semiconductor-photocatalyzed oxidation and heterogeneous Fenton-like reaction. Compared with the semiconductor photocatalysis, the photodecomposition rate of RhB was improved about 5 times when the simultaneous presence of the nanoparticles and H2O2, and a possible degradation mechanism was proposed.

Hierarchically structured nickel oxide microspheres were acquired through calcination of the hydroxide precursor at 400 °C for 4 h. The phase and morphology of the products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and field emission scanning electronic microscopy (FE-SEM). The synthesized products are pure phase with high crystallinity. And the hierarchical structures assembled from the nanoflakes with a thickness of 50 nm have a considerably large specific surface area (165.3 m2 g−1). The adsorption capacity and photocatalytic activity of the hierarchically structured NiO were evaluated using direct fast bordeaux as target pollutant, indicating a high decolorization rate. The effect of pH on the decolorization rate was also analyzed. The electrochemical behavior of NiO as anode material for lithium ion batteries was investigated. The excellent photocatalytic and electrochemical performances of NiO microspheres can be attributed to the unique hierarchical structures.

Wormlike GdFeO3 (GFO) nanoparticles were synthesized by a glycol-assisted sol–gel rapid calcination process. The as-synthesized GdFeO3 was characterized by X-ray diffraction, transmission electron microscopy, differential scanning calorimeter and thermogravimetric analysis, Fourier transformed infrared spectroscopy, and UV–vis absorption spectroscopy. The visible-light-responsive photocatalytic activity of GdFeO3 nanoparticles was evaluated by the photodegradation of Rhodamine B under visible light. The synergism of semiconductor-photocatalyzed oxidation and heterogeneous photo-Fenton-like reaction can markedly promote the photodegradation with a booming catalytic activity (k = 1.2814 h–1). Compared with the bulk, the catalytic activity of the GFO–H2O2 system was improved about 80 times. Meanwhile, the glass carbon electrode decorated with the resulting nanoparticles was used to examine the electrocatalytic behavior for p-nitrophenol reduction in a basic solution. The results show the obtained GdFeO3 nanoparticles with excellent photocatalytic and electrocatalytic activities.