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Z-scheme heterostructure photocatalysts for the transfer and separation efficiency of carriers are increasingly popular. CdS nanoparticle decorated three-dimensional (3D) flower-like Zn3(PO4)2 nanostructures were prepared through a simple hydrothermal route and precipitation methods. The CdS/Zn3(PO4)2 heteronanostructures were characterized through X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), UV-visible light spectroscopy (UV-vis), photoluminescence (PL) spectroscopy and photoelectrochemical measurements. The results showed that the three-dimensional flower-like structure of Zn3(PO4)2 composed of two-dimensional nanoplates and CdS/Zn3(PO4)2 heteronanostructures was obtained. The results of the Mott–Schottky measurements and the active species trapping experiments suggested that a Z-scheme system between the CdS nanoparticles and Zn3(PO4)2 nanoplates was formed. Meanwhile, the CdS/Zn3(PO4)2 heteronanostructures exhibited much higher photocatalytic activity for the degradation of MB under visible light, and that of the CdS/Zn3(PO4)2-13 heteronanostructure with excellent photocatalytic stability is nearly 3.04 times higher than that of pure Zn3(PO4)2 nanostructures. [ABSTRACT FROM AUTHOR]

The green treatment of dye wastewater has always been a research hotspot in the environmental field. The photocatalytic technology is considered to be a simple and effective strategy to remove dyes in wastewater. A new type of NiWO4/WO3 Z-scheme heterojunction microspheres were synthesized by a simple hydrothermal method and impregnation-calcination process. The crystal structure, microscopic morphology, optical and electrochemical properties of the samples were systematically characterized. The photocatalytic activity of methylene blue (MB) was studied by visible light irradiation. The results show that the direct Z-scheme heterojunction formed by NiWO4/WO3 effectively reduces the transfer resistance of photogenerated carriers and improves the separation efficiency of photogenerated carriers. The degradation rates of NiWO4/WO3-4 Z-scheme heterojunction microspheres to MB dye are 1.8 and 3.2 times higher than that of pure WO3·2H2O and WO3 microspheres, respectively. Combined with the Mott–Schottky curve and the active species capture experiments, a possible Z-scheme photogenerated carrier transfer mechanism is proposed. This study provides a method for the development and design of Z-scheme heterojunction photocatalysts in the field of wastewater purification. [ABSTRACT FROM AUTHOR]

Pd decorated TiO 2 nanocrystal with exposed (001) facets was synthesized via solvothermal hydrolysis combining photoreduction deposition route, which exhibited a great enhancement in activity and stability of photocatalytic selective alcohol oxidations under UV light irradiation in aqueous medium. The superior activity of Pd decorated TiO 2 nanocrystal with exposed (001) facets was attributed to the synergistic promoting effects of the following factors: firstly, the exposed (001) facets with higher surface energy facilitated the activation of reactant molecules and the photocatalytic oxidation; secondly, the increased oxygen vacancies and enhanced O 2 adsorption on (001) facets could trap photoelectrons and thus, inhibit their recombination with holes; thirdly, the decoration with Pd nanoparticles effectively reduce the photocharge recombination rate by capturing photoelectrons. Meanwhile, this photocatalyst displayed excellent durability owning to the strong Pd-TiO 2 interaction against deactivation caused by either Pd leaching or Pd aggregation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The peptides decorated g-C 3 N 4 hybrids were synthesized for enhanced photocatalytic activities. • The R-CN composite demonstrated excellent photocatalytic hydrogen under the visible light. • The strained heptazine planes in the g-C 3 N 4 structure is formed by the peptide deposition. • The electron redistribution and delocalization in the R-CN composite lead the band gap reduction. This work demonstrated the synthesis of peptides decorated porous g-C 3 N 4 hybrids (R-CN) for the enhanced photocatalytic H 2 production, where the 14-mer peptides were effectively deposited on g-C 3 N 4 nanosheets by electrostatic interaction. The prepared R-CN hybrid composite shows the enhanced visible light absorption due to the modulation of electronic structures of g-C 3 N 4 by the interaction between peptides and g-C 3 N 4. Therefore, the R-CN hybrid composite demonstrated the excellent photocatalytic H 2 production with yield of 2018 μmol·g−1·h−1 under the visible light irradiation, which is 14-time higher than that of pristine g-C 3 N 4. The theoretical study shows that the strained heptazine planes in the g-C 3 N 4 structure is formed in the R-CN hybrid composites by the electrostatic interaction between the positively charged amine group of peptides and the negatively charged edge N atom of g-C 3 N 4. Thus, the electron redistribution and delocalization in the R-CN composite lead the band gap reduction, build-in electrical field and electronic modulation. Therefore, the R-CN composites shows the enhanced charge separation and the optimized free energy of reaction intermediates for the excellent photocatalytic activities. These results are confirmed from the experimental measurements and the MD and DFT computations study. This work provides an effective strategy to design biomaterial-based metal-free photocatalysts for H 2 production. [ABSTRACT FROM AUTHOR]

TiO 2 with an enhanced photocatalytic activity was biomineralized using a lysozyme (LYZ)–polystyrene (PS) biotemplate. We present a novel and green biomineralization route for TiO 2 particles to increase the photodegradation efficiency of rhodamine B (RhB) under visible light irradiation. The LYZ–PS template was constructed via a facile passive adsorption process under an ambient environment. The electrostatic interaction between PS and LYZ allowed LYZ–PS as a rigid template to function as a nucleation core to induce the biomineralization of TiO 2 particles. The LYZ–PS template not only enabled the empty structure in the particles during calcination but also provided a higher nitrogen content in the final TiO 2 photocatalyst. The LYZ–PS templated TiO 2 exhibited improved photocatalytic activity with au. 98% degradation of RhB after 80 min under solar light irradiation. The enhanced photocatalytic performance can be attributed to the synergetic effect of morphology, crystallinity and band gap. [Display omitted] • Lysozyme (LYZ)–polystyrene (PS) template was prepared by passive adsorption method. • LYZ–PS template function as a nucleation core to induce the TiO 2 biomineralization. • LYZ–PS tailored the morphology and crystallinity of TiO 2 and provided nitrogen source. • LYZ–PS–TiO 2 exhibited enhanced photodegradation efficiency on RhB under visible light. [ABSTRACT FROM AUTHOR]