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Co <sub/>3</sub> O <sub/>4</sub> nanoparticles decorated Ag <sub/>3</sub> PO <sub/>4</sub> as heterostructure for improving solar-light-driven photocatalysis
摘要： As a common photocatalytic material, Ag3PO4 still faces the challenge including the fast recombination of photo-generated electron-hole (e--h+) pairs. In this work, we prepared Co3O4/Ag3PO4 heterojunction with good optical properties by an in-situ precipitation method. Compared to pure Ag3PO4, the Co3O4/Ag3PO4 exhibited greatly improved photocatalytic activities for degradation methylene blue (MB) and bisphenol A (BPA) under the visible light irradiation. Here, the degradation rate of MB could reach up to 12% which is about 35% higher than that of pure Ag3PO4, after 18 min irradiation. The degradation rate of BPA could reach up to 33% which is about 45% higher than the pure Ag3PO4. This work may provide insight for finding a new Ag3PO4 photocatalyst for promoting the photocatalytic performance
关键词： solar-light-driven,degradation,heterostructure,Co3O4/Ag3PO4,photocatalysis
更新于2025-09-04 15:30:14
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Enhanced visible-light-driven photocatalysis of Bi2YO4Cl heterostructures functionallized by bimetallic RhNi nanoparticles
摘要： Bismuth-based Sillen-Aurivillius compounds are being explored as efficient photocatalyst materials for the degradation of organic pollutants due to their unique layered structure that favours effective separation of electron-hole pairs. In this work, we synthesized Sillen-Aurivillius-related Bi2YO4Cl with the bandgap of 2.5 eV by a simple solid-state reaction and sensitized with rhodium nickel (RhNi) nanoparticles (NPs) to form the RhNi/Bi2YO4Cl heterostructure. Photocatalytic activities of BiOCl, Bi2YO4Cl and the RhNi/Bi2YO4Cl heterostructure were examined for the degradation of rhodamine-6G under visible-light illumination. Results demonstrated that the photocatalytic dye degradation efficiency of RhNi/Bi2YO4Cl heterostructures is higher than those of BiOCl and Bi2YO4Cl, attributed to the synergistic molecular-scale alloying effect of bimetallic RhNi NPs. The plausible mechanism for the degradation of rhodamine-6G and the effective electron-hole pair utilization mechanism were discussed.
关键词： Bi2YO4Cl,RhNi catalyst,rhodamine-6G,photocatalysis,BiOCl
更新于2025-09-04 15:30:14
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Noble metal nanoparticle-functionalized Zr-metal organic frameworks with excellent photocatalytic performance
摘要： Noble metal nanoparticles (NPs) functionalized MOFs are attractive materials for photocatalytic reactions, and outstanding catalytic performances can be expected, especially when they have intrinsically matched crystal faces between metals and MOFs. This study discovered that the photocatalytic oxidation of aromatic alcohols to aldehydes was enhanced over Au/UiO-66-NH2 or Au/UiO-66 but suppressed over Pt loaded counterparts, whereas the reduction of Cr(VI) was boosted over both two catalysts. In reactions, the conversion of benzyl alcohol was 17.1% over UiO-66-NH2 and 7.6% over UiO-66, and an enhanced conversion was obtained over Au/UiO-66-NH2 (30.5%) and Au/UiO-66 (24.1%). However, the conversion was decreased over Pt/UiO-66-NH2 (9.3%) and Pt/UiO-66 (<1%). Experimental results revealed strong correlations between Zr-MOFs and loaded metal NPs, as Zr centers promoted the formation of Pt(200) planes that suppressed the production of (cid:1)O2 intermediates to oxidize aromatic alcohols, whereas Pt(200) exhibited no effect on the Cr(VI) reduction triggered by photo-induced electrons. The findings in this study on constructing noble metal NPs functionalized Zr-MOFs catalysts with specially-matched crystal structures and on distinguishing photocatalytic mechanisms on oxidation of alcohols and reduction of Cr(VI) would provide valuable information for designer (photo)catalysts based on MOFs and their applications in such as catalysis and environmental remediation.
关键词： Photocatalysis,Zr-MOFs,Metal loading,Pt(200) plane
更新于2025-09-04 15:30:14
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A Mechanistic View of the Main Current Issues in Photocatalytic CO2 Reduction
摘要： After 40 years of research on photocatalytic CO2 reduction, there are still many unknowns about its mechanistic aspects even for the most common TiO2-based photocatalytic systems. These uncertainties include the pathways inducing visible-light activity in wide-band-gap semiconductors; the charge transfer between semiconductors and plasmonic metal nanoparticles; the unambiguous determination of the origin of C-bearing products; the very first step in the activation of the CO2 molecule; the factors determining the selectivity; the reasons of photocatalyst deactivation; the closure of the catalytic cycle by the hole-scavenging reagent; and the detailed reaction pathways and the most suitable techniques for their determination. This perspective discusses these controversial issues based on the most relevant investigations reported so far. For that purpose, we have tried to view the complex CO2 reduction in a holistic manner, considering today’s state-of-the-art approaches, strategies and techniques for the study of one of the hottest topics in energy research.
关键词： Advanced characterization techniques,CO2 reduction,Photocatalysis,Artificial photosynthesis,Reaction mechanism,Charge transfer
更新于2025-09-04 15:30:14
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Molecular Doping of Electrochemically Prepared Triazine-Based Carbon Nitride by 2,4,6-Triaminopyrimidine for Improved Photocatalytic Properties
摘要： Copolymerization of melamine with 2,4,6-triaminopyrimidine (TAP) in an electrochemically induced polymerization process leads to the formation of molecular doped poly(triazine imide) (PTI). The polymerization is based on the electrolysis of water and evolving radicals during this process. The incorporation of TAP is shown by techniques such as elemental analysis, Fourier transform infrared and NMR spectroscopies, and powder X-ray diffraction, and it is shown that the carbon content can be tuned by the variation of the molar ratio of the two precursors. This incorporation of TAP directly influences the electronic structure of PTI and as a result, a red shift can be observed in UV?vis spectroscopy. The smaller band gap and the increased absorption in the visible range lead to improved photocatalytic properties. In dye degradation experiments, it was possible to observe an increase of the rate of the degradation of methylene blue by a factor of 4 in comparison to undoped PTI or 7 if compared to melon.
关键词： 2,4,6-triaminopyrimidine,photocatalysis,electrochemical synthesis,molecular doping,poly(triazine imide)
更新于2025-09-04 15:30:14
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Selective growth of palladium nanocrystals on the (100) facets of truncated octahedral Cu <sub/>2</sub> O for UV plasmonic photocatalysis
摘要： We report Pd-based UV plasmon-enhanced photocatalysis and its hot electron effect. The selective crystalline growth of Pd nanocrystals on the (100) facets of truncated octahedral Cu2O was conducted and proved. The photocatalytic activities of Pd/Cu2O at λ = 254 nm and at λ = 365 nm respectively had ca. 18- and 10-fold enhancements due to the hot electron effect.
关键词： palladium nanocrystals,UV plasmonic photocatalysis,hot electron effect,Cu2O
更新于2025-09-04 15:30:14
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Calcination Effects and Photocatalytic Activity of Porous SiO2-TiO2 Material
摘要： A porous SiO2-TiO2 photocatalyst was prepared through co-sol-gel method using PEG1000 template for photocatalytic degradation of methyl orange. Photocatalytic degradation was conducted after adsorption equilibrium to identify the contribution of both adsorption and photocatalytic degradation. The optimum calcination condition for the porous SiO2-TiO2 is 500 °C for 3 h. The adsorption of methyl orange on the photocatalyst has no apparent change in the whole temperature range. Nearly 96.5 % of the initial methyl orange is removed in 100 min under UV light irradiation with the existence of the porous SiO2-TiO2. Methyl orange degradation follows the first order kinetics equation. The azo and benzene structure are degraded into small molecules during photocatalytic oxidation process.
关键词： Photocatalysis,Composite,SiO2,TiO2
更新于2025-09-04 15:30:14
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Polydopamine and Barbituric Acid Co-Modified Carbon Nitride Nanospheres for Highly Active and Selective Photocatalytic CO <sub/>2</sub> Reduction
摘要： Carbon nitride nanospheres modified with polydopamine and barbituric acid (BA-CNS-PDA) were successfully prepared by following a template-copolymerization and post-modification strategy. The photocatalytic CO2 reduction was carried out using BA-CNS-PDA as photocatalyst, Co(bpy)3 as the cocatalyst and TEOA as the sacrificial electron donor. The productivity and selectivity for photocatalytic reduction of CO2 to CO on BA20-CNS-PDA15 under visible-light for 4 h were measured to be 158 μmol and 86.0 %, respectively, and are nearly 5 and 1.5 times, respectively, that of unmodified CNS. Optical characterization indicates that the outstanding photocatalytic CO2 reduction performance is a result of improved charge separation and transfer due to copolymerization with barbituric acid and enhanced visible light absorption due to polydopamine. The adsorption isotherm of CO2 demonstrates that polydopamine increase CO2 adsorption capacity and promote CO2 activation due to the presence of the amino groups.
关键词： Photocatalysis,Nitrides,CO2 reduction,Nanostructures
更新于2025-09-04 15:30:14
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Surfactant Free Hydrothermal Synthesis of Zn <sub/>2</sub> SnO <sub/>4</sub> Nanoparticles and Their Functional Properties
摘要： A simple, low temperature, cost effective, surfactant free and scalable synthesis of technologically important Zn2SnO4 (ZTO) nanoparticles with controllable size and shape has been developed. X-ray diffraction (XRD), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) of the synthesized ZTO nanoparticles revealed the formation of highly pure crystalline ZTO phase with the spinel-like structure. The Raman spectrum of the sample was dominated by the A1g vibration mode of pure ZTO phase. From UV–Vis absorption measurements, a band gap (Eg) of 3.78 eV was determined. The photocatalytic activity of the ZTO nanoparticles was evaluated for the photodegradation of methylene blue (MB) under UV-Vis light irradiation. The ZTO-assisted photocatalytic degradation of MB is complete in 25 minutes indicating good photocatalytic activity of ZTO. Mass spectrometric (MS) analysis of degradation intermediates isolated at regular time intervals reveals the presence of azure A, azure B and thionin which are demethylated products of the MB, indicating that the degradation is initiated by demethylation of the molecule.
关键词： Nanoparticles,Photocatalysis,Zn2SnO4,Transmission electron microscopy,Hydrothermal Synthesis
更新于2025-09-04 15:30:14
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Two bimetallic metal–organic frameworks capable of direct photocatalytic degradation of dyes under visible light
摘要： Two bimetallic metal–organic frameworks (MOFs), specifically {2[LiM(TDA)2(DMF)]·NH2+(CH3)2}n (M = Co (HNU-29) or Zn (HNU-30), TDA = 2,5-thiophenedicarboxylate), were synthesized by solvothermal methods. X-ray crystal structures of the two MOFs showed them to be isostructural. Thus, in both cases, the metal secondary building units were connected by TDA2? ligands to form a 3D framework whose structure can be simplified to the twofold interpenetrated dia net. HNU-29 showed excellent photocatalytic activity for the degradation of methylene blue (MB) under visible light even without the addition of H2O2 as an electron acceptor, remaining stable even after several cycles of reuse. The MB degradation followed first-order kinetics, and the photocatalytic degradation mechanism was found to be related to the effective ligand-to-metal charge transfer within the framework.
关键词： Photocatalysis,Methylene blue,Metal–organic frameworks,Visible light,Dye degradation
更新于2025-09-04 15:30:14