修车大队一品楼qm论坛51一品茶楼论坛,栖凤楼品茶全国楼凤app软件 ,栖凤阁全国论坛入口,广州百花丛bhc论坛杭州百花坊妃子阁

oe1(光电查) - 科学论文

43 条数据
?? 中文(中国)
  • Rationally Designed Fe2O3/GO/WO3 Z-Scheme Photocatalyst for Enhanced Solar light Photocatalytic Water Remediation

    摘要: A novel ternary Fe2O3/GO/WO3 all-solid-state Z-Scheme photocatalyst was rationally designed. Structural, morphological, optical and electronic properties of the synthesized nanocomposite were investigated by XRD, SEM, TEM, UV-vis Diffuse Reflectance and Raman spectroscopy. The results revealed the successful synthesis of the nanocomposite materials. Uniquely, double absorption edges at 2.0 and 2.3 eV for Fe2O3/WO3 and triple absorption edges at 1.5, 1.8 and 2.1 eV for Fe2O3/GO/WO3 were investigated for the first time. Lower absorption band edges dominated for both Fe2O3/WO3 and Fe2O3/GO/WO3, while higher absorption edges dominated for pure nanomaterials. The enhanced interaction among GO, Fe2O3 and WO3 matrix explained the reduction in the CB energy leading to efficient electron separation and transformation and consequently improving the photocatalytic activity. The visible light photocatalytic performance of Fe2O3/GO/WO3 nanocomposites were evaluated for degradation of methylene blue (MB) and crystal violet (CV) dyes as model water pollutants. The photocatalytic activity for degradation of both dyes was found to be greatly enhanced in the presence of ternary Fe2O3/GO/WO3 nanocomposite as compared to nanocomposite systems of Fe2O3/WO3, WO3/GO and Fe2O3/GO or pure Fe2O3 and WO3 nanomaterials. The enhancement in the photocatalytic performance of ternary Fe2O3/GO/WO3 nanocomposite was proven to be due to the all-solid-state Z-Scheme in which the photogenerated electrons in the CB of photosystem I (WO3) transferred through GO mediator and recombined with the photogenerated holes in the VB of Fe2O3 (photosystem II). So that, the electron-hole pair recombination can be suppressed in both systems. Moreover, the photocatalytic activity of the best Fe2O3/GO/WO3 nanocomposite (FGW 30) has been tested for the degradation of phenol. The results show that 95.4 % of phenol was degraded in 120 minutes. Thus, this study provides an efficient green Z-Scheme photocatalyst for water remediation utilizing solar light.

    关键词: solar light photocatalysis,organic dyes degradation,all-solid-state Z-Scheme,Ternary Fe2O3/GO/WO3,phenol mineralization

    更新于2025-11-14 15:26:12

  • Structural and photocatalytic properties of co-doped hybrid ZrO2–TiO2 photocatalysts

    摘要: In this study, pure TiO2, ZrO2, and hybrid ZrO2–TiO2 photocatalysts were synthesized through solgel process and calcined at three different temperatures. The synthesized photocatalysts were characterized using powder X-ray diffraction (PXRD), field-emission scanning electron microscopy (FESEM), Brunauer–Emmet–Teller (BET), ultraviolet–visible (UV–Vis) spectrometer, and photoluminescence (PL) spectrometer. The PXRD patterns show that the rutile phase of TiO2 was suppressed through co-doping with ZrO2 and produced small crystallite size. The hybrid photocatalysts with small crystallite size recorded the highest surface area of 114.7 m2/g compared to pure TiO2 and ZrO2 photocatalysts as confirmed by BET analysis. Irregular size and shape was observed in the hybrid photocatalysts compared to spherical shape and size in TiO2 and flaky shape in ZrO2 as shown by the FESEM images. The optical properties of the photocatalysts investigated using UV–Vis spectroscopy showed a decrease in band gap energy of pure TiO2 through linear extrapolation from the Tauc’s plot despite the slightly higher band gap energy of the hybrid photocatalysts. However, PL analysis showed that doping of ZrO2 into TiO2 increased the separation efficiency of the electron–hole pairs and enhanced the photocatalytic activity. The phenol degradation of the hybrid ZrO2–TiO2 photocatalysts was higher compared to those of the pure TiO2 and ZrO2.

    关键词: Hybrid TiO2–ZrO2 photocatalysts,Solgel,Phenol degradation

    更新于2025-11-14 15:25:21

  • 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

  • Photocatalytic Degradation of Methylene Blue and Phenol Using TiO2/Activated-Carbon Composite Catalysts

    摘要: Photocatalytic degradation of methylene blue and phenol were conducted separately in aqueous solutions using titania-activated carbon composites. Activated carbon composites of different textural features and light of different wavelength or energy were used in order explore their effects on the performance of titania-activated carbon catalysts. The catalysts (TiAC1, TiAC2 and TiAC3) were prepared by impregnating activated carbon supports with an aqueous suspension of titanium precursor (TiO2). The catalysts were characterized using BET, XRD and FTIR. The diffraction pattern showed strong peaks that are assigned to titanium anatase phase and weaker peaks that indicated low rutile phase. The FTIR showed broad peaks of Ti-O-Ti linkages in TiO2 particles. The photocatalytic degradation of methylene blue and phenol was performed separately in visible light and UV irradiation of different wavelengths. Adsorption was dominant in the case of methylene blue removal while photodecomposition was more pronounced in the case of phenol removal.

    关键词: Photocatalysis,Phenol,Methylene blue,Titania,Activated carbon,Precursors

    更新于2025-09-23 15:23:52

  • Photocatalytic degradation of phenol by LaFeO3 nanocrystalline synthesized by gel combustion method via citric acid route

    摘要: Focusing on the photocatalytic degradation of phenol under visible light, the synthesized lanthanum orthoferrites (LaFeO3) by gel combustion method using citric acid as sacrificial agent were investigated. With the highest reaction temperature of 200 °C, the physicochemical properties of synthesized samples were characterized by X-Ray diffraction (XRD) analysis, Brunauer–Emmet–Teller (BET), and Energy Dispersive X-Ray spectroscopy (EDS). On the other hand, UV–Vis spectroscopy analysis was carried out to determine the phenol photodegradation activities and mechanism. The results suggested the well-defined LaFeO3 nanocrystals with specific area of 28 m2 g?1 were successfully synthesized. Besides that, variations in operating parameters such as pH, catalyst dosage and initial concentration of phenol in synthetic wastewater were also examined. In conclusion, LaFeO3 nanocrystalline exhibited an exceptional photocatalytic activity for phenol degradation, thus providing a perfect alternative for pharmaceutical wastewater treatment.

    关键词: Citric acid,Photocatalytic activity,Lanthanum orthoferrite,Phenol,Gel combustion

    更新于2025-09-23 15:23:52

  • A Complete Active Space Self-Consistent Field and Density Functional Theory Study of S0, T1, S1 States of Five Phenol ortho-Derivatives

    摘要: The low-lying electronic states (S0, S1 and T1) of five phenol ortho-derivatives have been studied by the complete active space self-consistent field (CASSCF) and B3LYP methods. Structure optimizations indicate that the S1 structures of 2-nitrophenol, salicylaldehyde, 2-acetylphenol are H transfer structures, but those of salicylamide and salicylic acid not. The T1 structures are all H transfer structures. To these five phenol ortho-derivatives, all the transitions of S0→S1 and S0→T1 are come from the HOMO to LUMO orbital, and show π-π* transition characters. Additionally, ortho-effect is also discussed.

    关键词: Phenol o-derivatives,Complete active space self-consistent field,Density functional theory

    更新于2025-09-23 15:23:52

  • Efficient degradation of phenol using Sn4+ doped FeOCl as photo-Fenton catalyst

    摘要: Sn4+ doped FeOCl has been successfully synthetized as a sunlight-driven photo-Fenton catalyst, which shows that the catalytic activity of Sn4+/FeOCl (1.08% Sn4+ in the Sn4+/FeOCl) is a factor of 11.8 time higher than that of FeOCl. The doping of Sn4+ in FeOCl increases the optical adsorption and surface area of FeOCl. The decreased chemical bond strength of Fe-Cl in Sn4+/FeOCl effectively increases the number of exposed active sites (Fe-site and Sn-site), which boosts the production of ·OH radicals. The Sn-site shows higher catalytic activity than Fe-site. A synergistic mechanism for Sn4+/FeOCl is proposed for the enhanced catalytic performance.

    关键词: Solar energy materials,FeOCl,Phenol,Nanocomposites,Fenton reaction,Sn4+

    更新于2025-09-23 15:23:52

  • Synthesis and characterization of composites ZnZr for the photocatalytic degradation of phenolic molecules. Addition effect of ZrO <sub/>2</sub> over hydrozincite Zn <sub/>5</sub> (OH) <sub/>6</sub> (CO <sub/>3</sub> ) <sub/>2</sub>

    摘要: BACKGROUND: Composite materials ZrO2/Zn5(OH)6(CO3)2 were prepared in only one step by chemical coprecipitation and thermal hydrolysis of urea. ZrO2 was added at 5, 8 and 10 mol%. The samples were dried at 80°C and characterized by adsorption-desorption of N2 isotherms, XRD, SEM, techniques and DRS, UV-Vis, FTIR and XPS spectroscopies. The materials were assessed in the photodegradation of phenol and polychlorinated phenolic molecules under UV-light irradiation. The possible mechanism was discussed from studies that corroborated o discarded the formation of the species ?OH, ?O2- and h+. RESULTS: The addition of ZrO2 to Zn5(OH)6(CO3)2 resulted in a composite material with high photoactivity. Being the most efficient the sample with 8 mol% of ZrO2. The photodegradation enhancement was partly achieved by an increment in the specific surface area and principally due to localized states originated in the composite interphase which improve the charges transfer. It was found by XPS study that the ZrO2 addition increment the oxygen vacancies which enhance the organic molecule photodegradation via direct holes attack. CONCLUSION: The composite system ZnZr can be an excellent alternative for the persistent organic pollutants photodegradation due to the low cost, high stability and null toxicity of the support Zn5(OH)6(CO3)2.

    关键词: ZrO2,hydrozincite,phenol-chlorophenols photodegradation,composites

    更新于2025-09-23 15:23:52

  • Functionalization of silicon nanowires by iron oxide and copper for degradation of phenol

    摘要: Iron oxide (Fe3O4) and copper-functionalized silicon nanowires (SiNWs) from silicon powder mesh < 500 with a spherical structure have been successfully synthesized as a heterogeneous catalyst for the degradation of phenol. This synthesized catalyst was prepared by nanosilicon wire powders. SiNWs have attracted much attention due their potential application in nanoscale devices such as field effect transistors, chemical or biological sensors, battery electrodes and photovoltaics. The SiNW properties were reinforced by functionalization. The synthesis of this catalyst was done by an in situ method for the decoration of SiNWs. Magnetic metal oxide compounds have been chosen not only to accelerate the catalyst recovery but also to improve the time duration of pollution elimination. Also, Cu nanoparticles were added in order to evaluate the catalytic property. In this work, the maximum amount of phenol degradation was obtained near 99.99%. Hybrid surface morphologies were characterized by scanning electron microscopy, X-ray diffraction, transmission electron microscopy, the Brunauer–Emmette–Teller model and high-performance liquid chromatography.

    关键词: Mesoporous,Fe3O4–Cu-SiNWs catalyst,Phenol degradation,Sphere

    更新于2025-09-23 15:23:52

  • Triphenyl phosphate end-capped dicyanomethylene-4H-pyran as a near infrared fluorescent sensor for lysozyme in urine sample

    摘要: A dicyano-methylene-4H-pyran (DCM)-based fluorescent probe DCPOP was designed for detecting lysozyme in urine sample. DCPOP showed obvious NIR emission (> 650 nm) avoiding the background fluorescence of urine (450 ? 600 nm). Compared to its mimic (DCPO), DCPOP has a big end-capped triphenyl phosphate (TPP) moiety, which induced good stability in several aqueous with different pH value. Furthermore, the end-capped TPP moiety showed weak interaction with lysozyme, which could modulate the emission signals of DCPOP. As a result, DCPOP could detect the lysozyme in both PBS buffer and real urine samples.

    关键词: Fluorescent sensor,Near-infrared (NIR),Dicyano-methylene-4H-pyran-phenol (DCPO),Triphenyl phosphate end-cap,Lysozyme (Lys)

    更新于2025-09-23 15:23:52