- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Synthesis of yttrium doped BiOF/RGO composite for visible light: Photocatalytic applications
摘要： In this present work, yttrium doped bismuth oxy fluoride/reduced graphene oxide (Y-BiOF/RGO) composite was synthesized using a simple solvothermal method. As synthesized composite was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), UV–Vis diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) techniques. The photocatalytic property was evaluated towards the degradation of methylene blue (MB) dye under the visible-light irradiation. The characterization results highlighted that the efficient incorporation of both yttrium ions and RGO greatly reduced the recombination rate of BiOF and extended the visible-light absorption ability. As synergistic effects, the prepared Y-BiOF/RGO composite exhibited maximum degradation rate of 98% in 360 min, which is 6.5 times higher than pure BiOF. The clear mechanism for the enhanced photo-activity by Y-BiOF/RGO was discussed.
关键词： Semiconductors,BiOF,Photocatalysts,Yttrium,Graphene,Visible light
更新于2025-09-04 15:30:14
-
Carbon Nanotubes-Wrapped Urchin-Like Bi <sub/>2</sub> S <sub/>3</sub> Composites with Enhanced Photocatalytic Performance
摘要： The urchin-like Bi2S3/carbon nanotubes (Bi2S3 urchin/CNTs) composites were successfully synthesized by a microwave method. X-ray diffraction (XRD), Fourier Transform infrared spectra (FTIR), Raman spectra, diffused reflectance spectra (DRS) were used for the characterization of the obtained photocatalysts. The SEM and TEM morphology of Bi2S3 urchin/CNTs composites showed that urchin-like nanoparticles were assembled by many nanorods which grew radially from the center and nanorods were wrapped with CNTs on their end. The photocatalytic performance was studied by the degradation of methyl orange (MO) under visible light and the photodegradation efficiency of Bi2S3 urchin/CNTs hybrid materials exhibited significantly excellent photocatalytic activity. A possible mechanism for the photodegradation of MO was also suggested.
关键词： Photocatalysts.,Carbon Nanotubes
更新于2025-09-04 15:30:14
-
De novo design of organic photocatalysts: bithiophene derivatives for the visible-light induced C-H functionalization of heteroarenes
摘要： Herein, we report the de novo synthesis and characterization of a series of substituted bithiophene derivatives as novel inexpensive organic photocatalysts. DFT calculations were used to predict a priori their absorption spectra and redox potentials, which were then confirmed with empirical data. The photocatalytic activity of this novel class of organic photoredox catalyst was demonstrated in two visible-light mediated strategies for the C-H functionalization of heteroarenes. The implementation of these strategies in a continuous-flow photo-microreactor afforded moderate to excellent yields within few minutes of reaction time. Due to their straightforward synthesis, low cost and good photocatalytic properties we believe that the proposed bithiophene derivatives could be employed as a new class of organic photoredox catalysts.
关键词： Organic photocatalysts,C-H functionalization,Photoredox catalysis,DFT calculations,Continuous flow catalysis
更新于2025-09-04 15:30:14
-
Guiding the Design of Organic Photocatalyst for PET-RAFT Polymerization: Halogenated Xanthene Dyes
摘要： By examining structurally similar halogenated xanthene dyes, this study establishes a guiding principle for resolving structure?property?performance relationships in the photocontrolled PET-RAFT polymerization system (PET-RAFT: photoinduced electron/energy transfer?reversible addition?fragmentation chain transfer). We investigated the effect of the halogen substituents on the photophysical and electrochemical properties of the xanthene dyes acting as photocatalysts and their resultant effect on the performance of PET-RAFT polymerization. Consideration of the structure?property?performance relationships allowed design of a new xanthene photocatalyst, where its photocatalytic activity (oxygen tolerance and polymerization rate) was successfully optimized for PET-RAFT polymerization. We expect that this study will serve as a theoretical framework in broadly guiding the design of high performance photocatalysts for organic photocatalysis.
关键词： PET-RAFT polymerization,structure?property?performance relationships,oxygen tolerance,photocatalysts,halogenated xanthene dyes
更新于2025-09-04 15:30:14
-
Efficient synthesis of BiFeO3 by the microwave-assisted sol-gel method: “A” site influence on the photoelectrochemical activity of perovskites
摘要： BiFeO3 (BF) and LaFeO3 (LF) perovskites were synthesized using a microwave-assisted (MW) and sol-gel (SG) methods. XRD, XPS, TEM, UV-DRS techniques were applied to study physicochemical properties of perovskites. In addition, Incident Photon-to-Current Efficiency (IPCE) measurements, Linear Sweep Voltammetry (LSV) and impedance spectroscopy were used to characterize electrochemical properties of the material. The band gap energy increases in the following way: BF-MW (2.05 eV), LF-MW (2.18 eV), BF-SG (2.26 eV) and LF-SG (2.54 eV), demonstrating a remarkable influence of the synthesis method on the optical and electronic properties of the materials. Furthermore, XRD showed a significant impact of the synthesis methods on the crystal structure. Perovskites synthesized under WM irradiation showed a pure crystal structure compared to the perovskites prepared by SG method, which contained some admixtures. IPCE shows that LF-MW has a better charge separation ability compared to BF-MW. However, BF-SG showed the highest activity. Temperature programmed reduction tests (TPR) revealed a better ability of BiFeO3 to adsorb/desorb oxygen, compared to LaFeO3. XPS measurements pointed at the presence of Fe4+. Finally, the photocatalytic activity of the perovskites was tested in solar water-splitting as a function of the synthesis method and presence of Bi and La in “A” sites of the ABO3 perovskites. We postulate, that the Jahn-Teller distortion effect in LF-MW increases its catalytic activity by decreasing the binding energy compared to BF-MW.
关键词： Microwave-assisted synthesis,Jahn-Teller distortion,Photocatalysts,Photoelectrochemical water splitting,Perovskites
更新于2025-09-04 15:30:14