- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Acid-treated Fe-doped TiO2 as a high performance photocatalyst used for degradation of phenol under visible light irradiation
摘要： The photocatalytic activity of Fe-doped TiO2 nanoparticles is significantly increased by an acid-treatment process. The photocatalyst nanoparticles were prepared using sol–gel method with 0.5 mol% ratio of Fe:Ti in acidic pH of 3. The nanoparticles were structurally characterized by means of X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and diffuse reflectance spectroscopy (DRS). It was observed that the photocatalytic activity suffered from an iron oxide contaminating layer deposited on the surface of the nanoparticles. This contamination layer was removed using an HCl acid-treatment process. The photocatalytic activity using 500 mg/L of Fe0.5-TiO2 in a 10 mg/L of phenol solution increased significantly from 33% to 57% (about 73% increase in the performance), within 90 min of reaction time under visible light irradiation. This significant improvement was achieved by removing the iron oxide contamination layer from the surface of the nanoparticles and adjusting pH to mild acidic and basic pHs.
关键词： Kinetics,Iron doping,Phenol degradation,Visible light,Photocatalyst
更新于2025-11-14 15:25:21
-
Fabrication of MoS2/TiO2 heterostructure with enhanced photocatalytic activity
摘要： Two dimensional nanophotocatalysts MoS2/TiO2 with tunable decoration amount of MoS2 nanosheets were fabricated through hydrothermal route. The microstructure and photocatalytic behavior of as?prepared samples were characterized by X?ray diffraction, scanning electron microscope, transmission electron microscopy, UV?vis diffuse reflectance spectra, electrochemical workstation, dye degradation and water splitting experiment. The result shows that these composites exhibited enhanced photocatalytic activity for RhB degradation and hydrogen generation. Nearly 95% photocatalytic degradation of RhB was obtained for 2 h and 1.93 mmol g?1 h?1 of hydrogen production rate was achieved over MoS2/TiO2 at a MoS2 content of 10 wt%. And the corresponding photocurrent density of composite photoelectrode was 5?fold higher than that of pristine TiO2 architectures. It is believed that the boosting photocatalytic performance of heterostructure could be ascribed to the synergetic effect between the MoS2 and TiO2, which accelerated the separation and migration efficiency of charge carries as well as enhanced the light?harvest efficiency.
关键词： photocatalytic activity,photogenerated electron?hole pairs,heterostructure,photocatalyst,MoS2/TiO2
更新于2025-11-14 15:13:28
-
A sustainable multi-function biomorphic material for pollution remediation or UV absorption: Aerosol assisted preparation of highly porous ZnO-based materials from cork templates
摘要： For the first time, highly porous ZnO-based biomorphic materials were synthesised using cork as a natural sustainable template. In the first step, waste cork powder was pyrolysed and converted into inorganic carbon. This template was then infiltrated using a novel approach employing an aerosol of zinc-containing solutions. The infiltrated powders were calcined to convert the precursors into zinc oxide. Depending on temperature, these could form either a ZnO-graphite composite material, or pure ZnO. Their morphology, porosity, microstructure and composition were characterised; their optical band gap energies, ability to adsorb and photodegrade organic pollutants and UV absorption were also assessed. When heated to 350 oC they maintained the 3D porous cork structure, producing a graphite-containing composite material, with both physical adsorption and photocatalytic activity (Eg = 3.19 eV), suitable for environmental remediation. When heated to 700 oC, the powders were pure ZnO (no graphite), and they absorbed in the UV region, hence suitable for use as sunscreen. Doped ZnO ecoceramics were also produced, using silver and aluminium. An addition of 1 mol% Ag improved photocatalysis under solar light. Conversely, adding 2 mol% Al and calcining at 700 oC deactivated photocatalysis, but maintained strong UV absorption, producing a safer sunscreen material (no generation of free radicals). This is the first time that photocatalytic or UV absorption properties of any wood-derived biomorphic material or ecoceramic have been reported.
关键词： sunscreen.,zinc oxide,biomorphic/ecoceramic,aerosol,photocatalyst
更新于2025-10-22 19:40:53
-
A heterobimetallic Au(III)?Pt(II) photocatalyst for water reduction to hydrogen
摘要： A supramolecular complex, [Au(C^N^C)(C≡CC6H4C≡C)Pt(terpy)]+, has been synthesized as a photocatalyst for water reduction. This compound consists of a cyclometalated alkyngold(III) photosensitizer and a platinum(II) terpyridine complex bridged through a central phenylethynyl group.
关键词： heterobimetallic system,hydrogen evolution,photocatalyst
更新于2025-09-23 15:23:52
-
Solar Heterogeneous Photocatalytic Oxidation for Water and Wastewater Treatment: Problems and Challenges
摘要： Solar operation of heterogeneous photocatalytic oxidation reactors is looked at as a sustainable process for water and wastewater treatment, because it does not consume electric power and chemicals. However, there are still problems for technical-scale application. The problems addressed in this article are large area demand, water evaporation from open reactors and lack of simple photocatalyst recovery. An optimum solar reactor type is the parabolic compound collector reactor with borosilicate glass tubes. Challenges for further research are improvement in mass transfer as well as identification of novel photocatalysts which make use also of visible light, are efficient and stable, and are easy to be produced in an economically feasible way. Also the combination of photocatalysts with adsorbents is promising. Although membrane filtration processes have been successfully combined with solar photocatalytic oxidation and represent a safe barrier against spreading photocatalyst nanoparticles into the aquatic environment, more simple and less energy-consuming methods for photocatalyst recovery would be desirable.
关键词： Photocatalyst recovery,Novel photocatalysts,Solar photocatalytic oxidation,Photocatalysis adsorption hybrid process,Mass transfer
更新于2025-09-23 15:23:52
-
Enhanced Selectivity for Oriented Catalyzing Tetracycline by the Functional Inorganic Imprinted ZnFe <sub/>2</sub> O <sub/>4</sub> @Ag <sub/>3</sub> PO <sub/>4</sub> /SiO <sub/>2</sub> Photocatalyst with Excellent Stability
摘要： A novel functional inorganic imprinted ZnFe2O4@Ag3PO4/SiO2 photocatalyst was synthesized by a facile sol-gel method combined with the surface imprinting technique, which possessed excellent stability. By optimizing the amount of materials to determine the preferable addition amounts of tetraethoxysilane (TEOS) and tetracycline are 0.06 mL and 0.06 g, respectively. This as-prepared functional inorganic imprinted ZnFe2O4@Ag3PO4/SiO2 photocatalyst was proved to not only exhibit high photocatalytic activity (the photodegradation rate was 61.52% under the simulated sunlight irradiation of 60 min), but also possess a strong oriented ability to selectively recognize and photocatalyze tetracycline (the coe?cient of selectivity (kselectivity) was 5.14 for ciprofloxacin and 3.63 for gatifloxacin). Moreover, the functional inorganic imprinted ZnFe2O4@Ag3PO4/SiO2 photocatalyst prepared with SiO2 as the inorganic imprinted layer have good stability and can be recycled many times. This work not only puts forward a novel design idea of functional semiconductor materials but also is expected to be widely applied to the oriented catalysis for a target substance according to the practical requirement.
关键词： selectivity,stability,ZnFe2O4@Ag3PO4/SiO2,Inorganic imprinted photocatalyst,tetracycline oriented catalysis
更新于2025-09-23 15:23:52
-
Manganese dioxide nanoparticles/activated carbon composite as efficient UV and visible-light photocatalyst
摘要： Manganese dioxide nanoparticles/activated carbon (MnO2/AC) composites and manganese dioxide nanoparticles (MnO2 NPs) are prepared through chemical reduction method. Morphological study shows that MnO2 NPs had cylindrical and spherical shape. The morphological study also revealed that MnO2 NPs were well dispersed on AC while neat Mn NPs present both in dispersed and in agglomerated form. The FT-IR study confirms the synthesis of MnO2 NPs. Zetasizer study presented that the Mn NPs had uniform size and below 100 nm in size and had zeta potential of ? 20 mV, which represent its stability in the suspension form. The synthesized Mn/AC composite and Mn NPs were utilized as photocatalysts for the photodegradation of Congo red (CR) dye. The degradation study shows that MnO2/AC composite degraded CR dye more efficiently than MnO2 NPs under UV and normal light irradiation. The efficient degradation of dye by Mn/AC composite is due to the synergistic effect between dye adsorption on AC and rapid photodegradation by supported MnO2 NPs. The results revealed that Mn/AC composite degraded about 98.53% of CR dye within 5 min while MnO2 NPs degraded 66.57% of dye within the same irradiation time. The recycled catalyst also significantly degraded dye which verifies its sustainability. The effect of catalyst dosage and initial dye concentration was conducted. The degradation rate of dye was found drastically faster in tap water (in presence of catalyst), which might be due to the presence of various mineral ions in the tap water.
关键词： Manganese dioxide,nanoparticles,Activated carbon,Photodegradation,Photocatalyst,Congo red
更新于2025-09-23 15:23:52
-
Magnetically Recoverable PEI/Titanate@Fe3O4 Photocatalysts: Fabrication and Photocatalytic Properties
摘要： The magnetically separable ternary polyetherimide/titanate@Fe3O4 (PTF) photocatalysts of special heterostructure between magnetite (Fe3O4) microspheres and titanates nanosheets modified by polyetherimide (PEI) were successfully fabricated via a simple facile hydrothermal deposition method. The as-prepared photocatalysts were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, Transmission electron microscopy and UV-vis diffuse reflectance spectroscopy etc. The results showed that the as-fabricated material had a structure of Fe3O4 microspheres coated with titanates nanosheets modified by PEI. The special interfacial contact between 3D microsphere and 2D nanosheets in the nanoarchitectures was formed via electrostatic attraction. Furthermore, the resulted photocatalysts were tested by degradation reaction of methylene blue under visible light irradiation and demonstrated an enhanced performance than the pure Fe3O4 microspheres, and the photocatalytic activity enhanced with the molar ratio of Fe3O4 microspheres and modified titanate gradually, which was attributed to the expansion of the surface area and the different electrostatic contact between the Fe3O4 microspheres and titanate nanosheets. Moreover, the obtained results revealed the high yield magnetic separation and efficient reusability of PTF-5 (96.7%) over 3 times reuse.
关键词： titanate,Fe3O4 microspheres,recyclability,photocatalyst,polyetherimide
更新于2025-09-23 15:23:52
-
Hybrid composite of CuO with $$\hbox {g}\hbox {-C}_{3}\hbox {N}_{4}$$g-C3N4 as a photoactive catalyst: an efficient approach for the oxidation of alcohols
摘要： An eco-friendly method for the oxidative transformation of alcohols to their corresponding carbonyl compounds by using g-C3N4@CuO as a photoactive heterogeneous catalyst has been developed. The catalyst was characterized by SEM-EDX, TEM, BET surface area measurements, powder XRD, FTIR, photoluminescence and UV-Vis spectroscopy. It was found to be very effective for the conversion of both primary and secondary alcohols into aldehydes and ketones with excellent yields using tert-butyl hydrogen peroxide (TBHP) as oxidant at room temperature in the presence of visible light in aqueous medium. The catalyst can be separated from the reaction mixture by simple centrifugation and reused up to five cycles without significant loss in activity.
关键词： Nanocomposite,alcohol oxidation,copper oxide,photocatalyst,graphitic carbon nitride
更新于2025-09-23 15:23:52
-
Harnessing designer biotemplates for biomineralization of TiO2 with tunable photocatalytic activity
摘要： Biomineralization is a promising material synthesis strategy for environmentally benign production of nanostructured metal oxides. An important question is whether biomineralization can be used in the biomimetic synthesis of TiO2 with tunable photocatalytic properties that are conducive to diverse solar energy conversion applications. Here, we report the biomineralization of energy-state-modified TiO2 nanoparticles, where the critical properties closely related to their photocatalytic activity can be manipulated by tailoring the nature of the designer biotemplates. For this purpose, STB1 heptapeptide was employed as a nucleation center to induce TiO2 biomineralization. Three distinctive types of biomolecules (peptide, protein, and phage) were deliberately designed to contain the STB1 nucleation core at different local densities and intermolecular distances. The degree of substitutional nitrogen-doping and the morphology are all subject to the context-dependent differential availability of STB1 in the biomineralization milieu. Phage-induced biomineralization results in TiO2 with modified energy state and wire-like network morphology, which account for significantly enhanced charge dissociation/transport performance and high photocatalytic activity. This is the first study to report that a specific peptide with biomineralizing activity exerts differential impacts on the properties of resulting biomineralization products in a context-dependent manner, and will provide a powerful new strategy for tailoring of material properties via biomineralization.
关键词： Biomineralization,Titanium dioxide,Photocatalyst,in situ substitutional nitrogen-doping,Designer biotemplate
更新于2025-09-23 15:23:52