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In this work, a novel lignin-based carbon/ZnO (LC/ZnO) hybrid composite with excellent photocatalytic performance was prepared through a convenient and environment friendly method using alkali lignin (AL) as carbon source. The morphological, microstructure and optical properties of the as-prepared LC/ZnO hybrid composite was characterized with scanning electron microscope (SEM), X-ray diffraction (XRD), Raman and UV–vis. The resulting LC/ZnO hybrid is composed of highly dispersed ZnO nanoparticles embedded on a lignin-based carbon nanosheet, showing excellent photogenerated electrons and holes separation and migration efficiency. The photocatalytic activity of LC/ZnO was much higher than the pure ZnO. The LC/ZnO hybrid composite showed different photocatalytic mechanism for degradation of negative methyl orange (MO) and positive Rhodamine B (RhB). It showed that h + was the main photocatalytic active group during the degradation of MO, ·O 2 − and ·OH were the photocatalytic active groups during degradation of RhB. This reported photocatalyst with selective degradation of positive and negative organic dyes may have a great application prospect for photoelectric conversion and catalytic materials. Results of this work were of practical importance for high-valued utilization of lignin for carbon materials. [ABSTRACT FROM AUTHOR]

Highlights: [•] Plamonic Ag@AgCl was intercalated in the layered space of K4Nb6O17. [•] Ag@AgCl greatly increased visible light absorption for K4Nb6O17. [•] The plamonic photocatalysts exhibited enhanced activity for the degradation of RhB. [Copyright &y& Elsevier]

Highlights: [•] Plasmonic Ag@AgBr was intercalated in the layered space of K4Nb6O17. [•] Ag@AgBr greatly increased visible light absorption for K4Nb6O17. [•] The plasmonic photocatalysts exhibited enhanced activity for the degradation of RhB. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a novel plasmonic photocatalyst, Ag@AgI intercalated layered niobate, was synthesized via a microwave-assisted ion-exchange method. The composite materials prepared were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray fluorescence spectrometry (XRF), Brunauer–Emmett–Teller (BET) and ultraviolet–visible diffuse reflection spectra (UV–vis). The as-prepared plasmonic photocatalyst exhibited an enhanced and stable photocatalytic performance for the degradation of Rhodamine B (RhB) and up to 83% of RhB was degraded in 40min under visible light irradiation. The mechanism of separation of the photo-generated electrons and holes at the K4Nb6O17/Ag@AgI composite was discussed. [Copyright &y& Elsevier]

In this work, pompon-like structured g-C3N4/ZnO composite photocatalyst was fabricated by a two-step method and characterized through different characterization tools to determine the photophysical properties. It is discovered that the synthesized pompon-like g-C3N4/ZnO photocatalyst is composed of flake g-C3N4 coated on the pompon surface of ZnO to form a heterojunction structure. In the composite photocatalyst, the pompon ZnO has large surface area (41.81 m2/g) which can provide more reactive sites for composite catalysts, the g-C3N4 can absorb the visible light which can effectively expand the absorption range of the composite, and the heterostructure formed between g-C3N4 and pompon ZnO can effectively reduce the coincidence efficiency of photo-generated carriers. The photocatalytic performance of pompon-like g-C3N4/ZnO photocatalyst was evaluated by photocatalytic degradation of rhodamine B (RhB) organic dyes under simulated solar light irradiation and the optimum doping amount of g-C3N4 is 10%. The stability of the composite photocatalyst was tested by five runs of RhB photodegradation under simulated visible light. [ABSTRACT FROM AUTHOR]

Purpose The aim of this paper is to synthesize graphene-modified titanium dioxide (GR-TiO2) nanorod arrays nanocomposite films, so that these can enhance the photocatalytic properties of titanium dioxide and overcome the problem of difficult separation and recovery of photocatalysts.Design/methodology/approach The GR-TiO2 nanocomposite films were synthesized via hydrothermal method and spin-coating. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet–visible (UV-Vis) diffuse reflectance spectrum and Raman spectrum. The photocatalytic performance of the GR-TiO2 nanocomposite films for degrading Rhodamin B under ultraviolet (UV) was studied by a UV-Vis spectrophotometer. The photocatalytic enhancement mechanism of graphene was studied by photoelectrochemical analysis.Findings The introduction of graphene expanded the range of the optical response of TiO2 nanorod arrays, improving the separation efficiency of the photogenerated electron-hole pairs, and thus dramatically increasing its photocatalytic performance.Research limitations/implications A simple and novel way for synthesizing GR-TiO2 nanocomposite films has enhanced the photocatalytic performance of TiO2.Originality/value The photocatalyst synthesized is easy to separate and recycle in the process of photocatalytic reaction, so it is possible to achieve industrialization. [ABSTRACT FROM AUTHOR]