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Ternary metal sulfides normally have narrow band gap energy levels, leading to fast recombination of photogenerated carriers. The construction of heterojunctions is generally believed to boost the photogenerated carrier efficiency via capturing and transferring electrons, and thus improving the photocatalytic activity. In this paper, different ratios of AgInS2–SnIn4S8 composites were synthesized by a microwave-assisted hydrothermal method, and the molar ratio of SnIn4S8:AgInS2 = 0.5:1 is determined as the optimal ratio based on the experimental results of visible photocatalytic degradation of methyl orange (MO). Furthermore, AgIn5S8/AgInS2–SnIn4S8 composites were successfully prepared by changing the ratio of In, S element, and AgNO3. The component, structural morphology, and surface physicochemical properties of the composites were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, ultraviolet–visible diffuse reflectance absorption spectroscopy, and nitrogen adsorption–desorption tests. The results show that AgInS2 and AgIn5S8 are compounded with SnIn4S8 to form a heterogeneous structure. After the formation of heterogeneous structures, light absorption properties are changed and light absorption range is broadened due to stronger light absorption capacity in AgInS2 and AgIn5S8. As they have matched energy band structures, the electron transfer paths are increased and the e−–h+ lifetime is prolonged, which leads to enhanced photocatalytic performance of AgIn5S8/AgInS2–SnIn4S8 composites. Moreover, the formation of regular and homogeneous flower globose structure under the effect of microwave polarization also has an important contribution to the improvement of their photocatalytic performance. AgIn5S8/AgInS2–SnIn4S8 composites exhibit a certain degradation ability towards MO, and the degradation is almost complete within 180 min under visible light irradiation. Finally, through trapping experiments with the addition of different radical trapping agents and the ESR tests, photocatalytic active species are identified, and thus the possible photocatalytic reaction mechanism of AgIn5S8/AgInS2–SnIn4S8 composite is inferred. [ABSTRACT FROM AUTHOR]

Supramolecular self‐assembly is a promising strategy for stabilizing the photo‐sensitive components in photocatalysis. However, the underlying correlation between the enhanced photostability and supramolecular structure at the molecular level has not yet been fully understood. Herein, we develop a biomimetic vesicular membrane‐based polyporphyrin photocatalyst exhibiting excellent photocatalytic stability with at least activity time of 240 h in hydrogen generation. Time‐domain ab initio modelling together with transient absorption spectroscopy, visual frontier orbitals and Gibbs free energy calculation disclose that the ordered aggregation of porphyrin units in the vesicle membrane facilitates "hot" electron relaxation and the rapid dissipation of photo‐generated charges, thereby contributing to the longevity. This work deepens the molecular‐level understanding on photostability and photocatalytic mechanism of supramolecular photocatalysts. [ABSTRACT FROM AUTHOR]

The nanocomposite material C@Pt/MoS 2 @CdS was prepared by a simple microwave-assisted hydrothermal method combined with photoreduction method. The crystal structure, microstructure, and surface physical chemistry properties of the material were analyzed by X-ray diffraction (XRD), ultraviolet–visible diffuse reflectance absorption spectroscopy (UV–vis/DRS), X-ray photoelectron energy spectroscopy (XPS), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HR-TEM), nitrogen adsorption–desorption measurement, photoluminescence spectroscopy (PL), and electrochemical tests. As a result, this material has full-spectrum light absorption property and the composited CdS presents a good hexagonal phase. Moreover, the composite material presents a nanorod-like multi-layer core-shell structure, wherein the rod-like MoS 2 @CdS surface is covered with Pt and C. The formation of the multi-layer core-shell structure increases the specific surface area of as-composite material and strengthens its light absorption performance. The electrochemical impedance and transient photocurrent test results show that C@Pt/MoS 2 @CdS has the highest charge separation efficiency and enhanced photocurrent density compared with other systems. Photogenerated charge carriers have higher separation efficiency, and photogenerated electrons and holes exhibit longer life. During the photocatalysis experiments, the nanocomposite C@Pt/MoS 2 @CdS shows enhanced photodegradation activity under multi-modal photocatalytic experiments and excellent stability under visible light irradiation. In addition, C@Pt/MoS 2 @CdS has a strong photocatalytic water splitting ability. Under the same experimental conditions, its hydrogen production is 60 times that of commercially available P25. Through capture experiments, the reactive species in the photocatalytic reaction process were determined, and the possible photocatalytic reaction mechanism of this multi-layer core-shell C@Pt/MoS 2 @CdS nanocomposite was inferred. • Constructed a multi-layer core-shell structure photocatalytic composite material. • Improved the photocatalytic activity and stability of CdS-based photocatalyst. • The hydrogen production of C@Pt/MoS 2 @CdS was approximately 60 times that of commercially available P25. • Recombination rate of photogenerated charge carriers was effectively restrained. [ABSTRACT FROM AUTHOR]

In this paper, bayberry-like BiOBr/AgBr/LaPO 4 nanocomposites were synthesized by microwave-assisted hydrothermal treatment. The composition, structure, and morphology of BiOBr/AgBr/LaPO 4 nanocomposites were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV−visible diffuse reflectance (UV−vis/DRS), high-power transmission electron microscopy (HR-TEM), scanning electron microscopy (SEM), and N 2 adsorption−desorption measurements. The results show that the light absorption capacity of BiOBr/AgBr/LaPO 4 is clearly enhanced and that a bayberry-like structure is more likely to produce diffraction and reflection of light on the surfaces of composites. AgBr in the composite is capable of reducing to Ag0 after light irradiation. Ag0, acting as a charge-transfer mediator, can be the medium, thus forming a Z-scheme structure. At the same time, the surface plasmon resonance (SPR) effect of Ag0 exhibits higher activity in the simulated sunlight photocatalysis process in BiOBr/AgBr/LaPO 4. The photoelectrochemical methods further indicate that BiOBr/AgBr/LaPO 4 possesses the best electron−hole pair separation ability. Furthermore, two different interface electron transfer modes and multipathway photoelectron migration in the composite are determined. • A bayberry-like structure BiOBr/AgBr/LaPO 4 composite was synthesized. • AgBr in the composite is capable of reduction to form Ag0 after light irradiation. • The presence of Ag0 results in forming two different electron transport pathes. • Two electron transfer modes synergistically improve photocatalytic ability. [ABSTRACT FROM AUTHOR]

In general, quantum dots have the property of generating a plurality of charge carriers using hot electrons or using a single high-energy photon to improve the photocatalytic properties of the material. In this paper, CdS QDs@CdIn2S4/CdWO4 modified by CdS QDs was synthesized by the microwave-assisted hydrothermal method, and its composition, crystal structure, morphology, and surface physicochemical properties were well characterized. Electron microscopy results showed that CdS QDs@CdIn2S4/CdWO4 composite material exhibited a sheet structure with a length of ca. 350 nm and a width of ca. 50 nm, and CdS QDs uniformly distributes with a diameter of about 5 nm on the sheet structure. UV-visible diffuse reflectance tests showed that the combination of CdS QDs and CdIn2S4 can extend the light absorption range of CdWO4 to the visible region. Photoluminescence spectroscopy confirmed that CdS QDs had efficient electron transport capabilities. The multi-mode photocatalytic activity of CdS QDs@CdIn2S4/CdWO4 showed an excellent ability to degrade organic pollutants. Under the conditions of no co-catalyst and Na2S-Na2SO3 as the sacrificial agent, the hydrogen production of CdS QDs@CdIn2S4/CdWO4 can reach 221.3 μmol g−1 when exposed to visible light (λ > 420 nm) for 8 h.Multi-mode photocatalytic performances of CdS QDs modified CdIn2S4/CdWO4 nanocomposites with high electron transfer ability.Due to CdS QDs owning stronger electron transfer ability, CdS QDs@CdIn2S4/CdWO4 exhibited higher activity in multi-mode photocatalytic processes and the enhanced activity in splitting water into hydrogen. [ABSTRACT FROM AUTHOR]

[Display omitted] • This review presents the recent progress of photonic RE-MOFs creatively categorized by rare earth elements. • The inherent correlation between structure of RE-MOFs and their photonic properties are systematically and comprehensively presented. • Several key development directions of advanced photonic RE-MOFs are highlighted to guide the further design. Metal-organic frameworks (MOFs) represent an emerging category of porous crystalline materials, notable for their high porosity, adjustable pore sizes and elevated Lewis acid contents. Rare earth MOFs (RE-MOFs), a specific subset of MOFs, use rare earth ions or clusters as central metal linkers, rendering advantages of both MOFs and rare earth ions. The distinctive feature of rare earth ions with unfilled 4f electron shells endows them with elevated coordination numbers and unique photophysical characteristics. Besides, the diversity of ligands within MOF frameworks effectively channels the antenna effect to sensitize the rare earth ions, resulting in enhanced photon emission, making RE-MOFs a kind of promising material in the photonics field, including photocatalysis, fluorescent probes, light-emitting, temperature sensing, near infrared (NIR) emission and more. This review presents the recent progress of photonic RE-MOFs creatively categorized by rare earth elements to demonstrate their great potential in photonics. The inherent correlation between structure of RE-MOFs and their photonic properties are systematically and comprehensively discusssed. Moreover, we highlight several key development directions of advanced photonic RE-MOFs to guide the further design. [ABSTRACT FROM AUTHOR]