Activity For Methylene Blue Degradation Research Articles

Synthesis of Bi5O7I Nanoplates by PVP-Assisted Hydrothermal Method and Their Photocatalytic Activities

Bi5O7I nanoplates as visible-light-driven photocatalyst have been synthesized by PVP assisted hydrothermal method. The effect of weight content of PVP adding on phase, morphology, and photocatalytic activities of products has been studied. The products have been characterized by X-ray powder diffraction, Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). In this research, the products have been specified as pure phase of orthorhombic Bi5O7I structure. The size of Bi5O7I plates has been controlled by the weight content of PVP adding. Photocatalytic activities of the samples have been investigated through photodegradation of methylene blue (MB) under visible light irradiation. The Bi5O7I nanoplates synthesized in the solution containing 0.50 g PVP show the highest photocatalytic activity for degradation of MB under visible light. A mechanism for photodegradation of MB by Bi5O7I is explained according to experimental results.

Novel Pt-Ag3PO4/CdS/Chitosan Nanocomposite with Enhanced Photocatalytic and Biological Activities.

Decorating photocatalysts with noble metal nanoparticles (e.g., Pt) often increases the catalysts’ photocatalytic activity and biomedical properties. Here, a simple and inexpensive method has been developed to prepare a Pt-Ag3PO4/CdS/chitosan composite, which was characterized and used for the visible light-induced photocatalytic and antibacterial studies. This synthesized composite showed superior photocatalytic activity for methylene blue degradation as a hazardous pollutant (the maximum dye degradation was observed in 90 min of treatment) and killing of Gram positive bacterial (Staphylococcus aureus and Bacillus cereus) as well as Gram negative bacteria (Klebsiella pneumoniae, Salmonella typhimurium, Escherichia coli, and Pseudomonas aeruginosa) under visible light irradiation. The antibacterial activity of CdS, CdS/Ag3PO4, and Pt-Ag3PO4/CdS/chitosan against E. coli, Pseudomonas aeruginosa, Salmonella typhimurium, Klebsiella pneumoniae, Staphylococcus aureus, and Bacillus cereus showed the zone of inhibition (mm) under visible light and under dark conditions at a concentration of 20 µg mL−1. Furthermore, the cell viability of the CdS/chitosan, Ag3PO4, Ag3PO4/CdS/chitosan, and Pt-Ag3PO4/CdS/chitosan were investigated on the human embryonic kidney 293 cells (HEK-293), Henrietta Lacks (HeLa), human liver cancer cell line (HepG2), and pheochromocytoma (PC12) cell lines. In addition, the results indicated that the photodegradation rate for Pt-Ag3PO4/CdS/chitosan is 3.53 times higher than that of CdS and 1.73 times higher than that of the CdS/Ag3PO4 composite. Moreover, Pt-Ag3PO4/CdS/chitosan with an optimal amount of CdS killed large areas of different bacteria and different cells separately in a shorter time period under visible-light irradiation, which shows significantly higher efficiency than pure CdS and other CdS/Ag3PO4 composites. The superb performances of this composite are attributed to its privileged properties, such as retarded recombination of photoinduced electron/hole pairs and a large specific surface area, making Pt-Ag3PO4/CdS/chitosan a valuable composite that can be deployed for a range of important applications, such as visible light-induced photocatalysis and antibacterial activity.

Photocatalytic Activity of Graphene Oxide/Zinc Oxide Nanocomposites with Embedded Metal Nanoparticles for the Degradation of Organic Dyes.

Nanocomposite materials based on metal nanoparticles and graphene oxide (GO) have gained increasing attention for their wide range of potential applications in various materials science fields. In this study, an efficient photocatalyst based on GO/ZnO nanocomposites with embedded metal nanoparticles was successfully synthesized via a simple one-pot method. The synthesized nanocomposites were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. The photocatalytic activity of the synthesized nanocomposites was tested in the degradation of methylene blue (MB) dyes, as a model of water pollutants. A catalytic activity of 84% was achieved using a nanocomposite with a percentage of 3.125% GO, after 90 min sunlight irradiation. Furthermore, embedded copper and silver nanoparticles were used as dopants to study their effects on the activity of the photocatalyst. The GO–ZnO–Cu nanocomposite showed that the activity toward MB degradation was decreased by 50%, while a significant increase in the activity of MB degradation was achieved by the GO–ZnO–Ag nanocomposite. The removal efficiency of MB by the GO–ZnO–Ag nanocomposite reached 100% after 40 min of sunlight irradiation. Thus, the GO–ZnO–Ag nanocomposite has the potential to be an efficient adaptable photocatalyst for the photodegradation of organic dyes in industrial wastewater.

Photocatalytic activities of NiFe2O4/nitrogen-doping graphene oxide synthesized by hydrothermal method

The NiFe2O4/N-doped GO composites were successfully synthesized by the hydrothermal method from graphene oxide GO, urea, iron nitrat, and niken nitrat. GO was synthesized by a modifìied Hummers, method. The obtained composites exhibited photocatalytic activities for methylene blue degradation (MB) under visible light irradiation. MB photodegradation efficiency reaches 98% after 240 minutes of illumination. The NiFe2O4/N-doped GO (NF/GO-N) was of better photocatalytic than that of the NF and GO-N. A kinetic model was proposed by the combination of classical Langmuir-Hinshelwood kinetic model, the experimental data fit well the proposed model.

Textural and photocatalytic characteristics of iron-cobalt based nanocomposites supported on SBA-15: Synergistic effect between Fe2+ and Fe0 on photoactivity

The present work investigates the synthesis of iron-cobalt based nanocomposites supported on SBA-15 and shows a detailed study of their porosity and the photocatalytic activity in methylene blue degradation as a model dye. The textural characterization indicated the presence of interconnected pores after the impregnation process and insertion of Fe and Co on SBA-15. TEM images confirmed that the SBA-15 mesopores were partially filled by Fe and Co species after the addition of metals and an average particle size of 11 nm. The diffractograms revealed the formation of the Fe2SiO4 and CoFe2O4 phases for the O-SBA-15 sample (oxide supported on SBA-15) and the presence of the Fe7Co3 structure for the solid A-SBA-15 (alloy dispersed in mesoporous silica), indicating the phases that are partially blocking the mesopores. The photocatalysis results confirmed that the silica support is essential to optimize the photocatalytic activity of the Fe and Co species in the dye degradation, favoring the accessibility of active sites. The presence of the phase mixture, Fe2SiO4, and Fe7Co3, in OAM-SBA-15 (oxide and alloy supported on SBA-15) sample, favors the photocatalytic activity of methylene blue (MB) due to the synergistic effect between Fe2+ and Fe0. The degradation of the MB occur through a sequence of reactions both on the solid surface and on the solution.

Micro-patterned NiFe2O4/Fe–TiO2 composite films: Fabrication, hydrophilicity and application in visible-light-driven photocatalysis

The micro-patterning of NiFe2O4 (NFO) films was achieved by a photolithography-assisted chemical solution deposition technique without photoresists. Subsequently, the micro-patterned NFO films were combined with Fe3+-doping TiO2 (FTO) films and then novel micro-patterned NFO/FTO composite films were prepared. The structures, morphologies, hydrophilicity, and optical and visible-light photocatalytic performance of the micro-patterned NFO/FTO films were investigated. The results revealed that the micro-patterned NFO/FTO films exhibit the entire visible-light absorption, lower recombination of electrons and holes and improved hydrophilicity, resulting in higher visible-light photocatalytic activity for methylene blue degradation as compared to pure NFO and FTO films. In addition, the hydrophilicity and photocatalytic activity of the micro-patterned NFO/FTO films are strongly dependent on their pattern periods. More interestingly, the recyclability of the micro-patterned NFO/FTO film can be easily realized without the assistance of external magnet, and the catalytic activity does not decrease with cycle numbers.

Modified graphitic carbon nitride as the photocatalyst for wastewater treatment under visible light irradiation

Monomeric graphitic carbon nitride (g-C3N4) with abundant pores and suitable energy band structure was preparedbycalcining the mixture precursor at high temperature. Meanwhile, Zr/g-C3N4 and g-C3N4/ZnO photocatalysts were fabricated by doping the transition metal and constructing heterojunctions respectively, thereby overcoming the defects of monomeric carbon nitride and improving photocatalytic activity. Sample morphology and structure were characterized by TEM, BET, XRD, XPS, PL, and UV–vis DRS techniques, and the photocatalytic performance was evaluated by degradation of methylene blue (MB) under visible light irradiation. The results indicated that the different energy band structures of g-C3N4 from various precursors promoted the transfer and separation of photogenerated electron-hole pairs, thus improving the photocatalytic performance. Furthermore, Zr/g-C3N4 presented an outstanding photocatalytic activity for MB degradation, which was mainly due to the adjustment of band gap and the rapid movement of charge caused by the introduction of Zr. The g-C3N4/ZnO photocatalyst synthesized by co-melting and recrystallizing the composite precursors of two semiconductors performed well on the aspects of structure and performance, degrading 98.07% MB after 180 min of irradiation, 29% higher than that of g-C3N4-MU. The Z-scheme charge transfer route in g-C3N4/ZnO system integral to improving the separation of photocarriers and enhancing the oxidation of photocatalyst. Based on the radical scavenging experiment, the main oxidation species in the photocatalytic process was determined, and the photocatalytic mechanism was further speculated, which provided a future direction in highly efficient g-C3N4 photocatalyst design.

Synthesis of Heterostructure Au/ZnO Nanocomposites by Microwave-Assisted Deposition Method and Their Photocatalytic Activity in Methylene Blue Degradation

The heterostructure Au/ZnO composites with different Au content were successfully synthesized by sol-gel method and reduced Au3+ ions to metallic Au0 nanoparticles by microwave-assisted deposition method using ethylene glycol as reducing reagent. The crystal structure, morphology and chemical composition of prepared samples were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray (EDS) spectrometer and X-ray photoelectron spectroscopy (XPS). It found the good dispersed metallic face center cubic phase of Au nanoparticles were supported on hexagonal phase of ZnO microparticles. Photocatalytic activity of the heterostructure Au/ZnO nanocomposites were evaluated in the degradation of methylene blue (MB) solution under UV light irradiation. The 5% Au/ZnO composite showed the higher photocatalytic activity than pure ZnO and other Au/ZnO samples (2.5 and 10% Au/ZnO).

Synthesis of Walnut Shaped V₂O₃ Particles and Its Photocatalytic Activity for Methylene Blue Degradation Under Visible Light Irradiation.

In this study, walnut-shaped V₂O₃ particles with high photocatalytic activity in the visible light were synthesized by hydrothermal process. The V₂O₃ samples synthesized with the various temperature conditions of the hydrothermal process were characterized using XRD, SEM, TEM, UV-Visible spectrometer and N₂gas adsorption/desorption analysis. For investigating the photocatalytic performance of synthesized V₂O₃ particles in the visible light condition, photodegradation experiments of methylene blue (MB) solution under artificial sunlight irradiation was conducted. As a result, the V₂O₃ hydrothermal-synthesized at 280 °C was composed of pure V₂O₃ crystal structure and showed high photocatalytic activity for the degradation of MB dye in visible light.

One-Pot Synthesis of Magnetite-ZnO Nanocomposite and Its Photocatalytic Activity

Tri-octyl-amine is known for its potential to assist fabrication of metal and metal oxides nanoparticles. In this work elucidate the synthesis of magnetite-ZnO magnetic nano hybrid by simple one pot reflux method. The synthesized nanoparticles were characterized using X-ray diffraction (XRD), FE-SEM, HR-TEM, vibrating sample magnetometer (VSM), fourier transform infrared spectroscopy (FTIR) and UV–Vis spectroscopy. The X-ray diffraction results confirm the formation of magnetite-ZnO nanocomposites. IR data reveals the characteristic adsorption bands for oxide formation. Magnetic property of the prepared composite was determined by VSM. The photocatalytic activities was performed using methylene blue under UV irradiation. magnetite-ZnO nanocomposite were prepared by using one-pot reflux method with the help of trioctylamine as a solvent and hydrolysing agent. Structutral, morphological, optical and magnetic properties of synthesized nanoparticles were characterized with the help of XRD, FTIR, transmission electron microscopy (TEM), UV–Vis spectroscopy and VSM. X-ray diffraction results confirm the formation of magnetite-ZnO nanocomposites and IR data reveals the characteristic absorption bands for oxide formation. Magnetic property of the prepared composite was determined by VSM. Photocatalytic activities was performed using methylene blue (MB) under UV irradiation and absorbance of MB was found to be reduced for prepared nanocomposite when exposed for longer time. One-pot synthesized magnetite-ZnO nanocomposite and its photocatalytic activity for MB degradation.

Synthesis of Conducting Bifunctional Polyaniline@Mn-TiO2 Nanocomposites for Supercapacitor Electrode and Visible Light Driven Photocatalysis

We report a polyaniline-wrapped, manganese-doped titanium oxide (PANi/Mn-TiO2) nanoparticle composite for supercapacitor electrode and photocatalytic degradation. The PANi/Mn-TiO2 nanoparticles were synthesized using a solvothermal process, followed by oxidative polymerization of aniline. The structural properties of studied materials were confirmed by XRD, FTIR, HRTEM, FESEM, and UV visible spectroscopy. The as-prepared PANi/Mn-TiO2 nanoparticles revealed admirable electrochemical performance with a specific capacitance of 635.87 F g−1 at a current density of 1 A g−1 with a notable life cycle retention of 91% after 5000 charge/discharge cycles. Furthermore, the asymmetric cell with PANi/Mn-TiO2 as a positive electrode exhibited energy density of 18.66 W h kg−1 with excellent stability. Moreover, the PANi/Mn-TiO2 had promising photocatalytic activity for methylene blue degradation. The improved performance of PANi/Mn-TiO2 nanoparticles is attributed to the well-built synergetic effect of components that lead to significant reduction of band gap energy and charge transfer resistance, as revealed by UV visible spectroscopy and electrochemical impedance spectroscopy.

Synthesis of novel panchromatic porphyrin-squaraine dye and application towards TiO2 combined photocatalysis

Here with, a porphyrin-squaraine-based panchromatic sensitizer was designed, synthesized perfectly and confirmed by its spectral analysis. SP-TBU showed a wide energy absorption in the visible and NIR region, which is very important criteria for photocatalytic activity studies. With this dye, a new TiO2-porphyrin catalyst was prepared and studied using SEM, TEM, UV–vis diffused reflectance spectra, FT-IR spectroscopy, XPS, and EDS analyses. The photocatalytic activity for methylene blue degradation under visible light was studied and compared with the bare TiO2 and (4,4′,4″,4‴-(porphine-5,10,15,20-tetrayl)tetrakis(benzoic acid) with TiO2 (TCPP-TiO2) taken with and without the addition of H2O2. The order of the photocatalytic activity performance was TiO2 < TCPP-TiO2 < SP-TBU-TiO2. The fast and efficient activity of SP-TBU-TiO2 was due to its broad absorption ability. This is the first report of panchromatic TiO2-porphyrin-squarine photocatalysis.

Characterization and photocatalysis of visible-light-driven Dy-doped ZnO nanoparticles synthesized by tartaric acid-assisted combustion method

ZnO samples containing different contents of Dy dopant were synthesized by a tartaric acid-assisted combustion method. The as-synthesized samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The samples with and without Dy dopant were specified as hexagonal wurtzite ZnO. The particle sizes of samples were decreased from 113 ± 31 nm for ZnO to 15 ± 3 nm for 5 wt% Dy-doped ZnO but the specific surface areas were increased from 3.58 m2·g−1 for ZnO to 28.35 m2·g−1 for 5 wt% Dy-doped ZnO. Both ZnO and 5 wt% Dy-doped ZnO samples revealed the strongest vibration peak of Zn–O stretching vibration E2H mode. Photocatalytic activities of the as-prepared ZnO and Dy-doped ZnO nanoparticles were investigated through photodegradation of methylene blue (MB) under UV visible light irradiation. The 5 wt% Dy-doped ZnO nanoparticles showed the highest photocatalytic activity for MB degradation of 97% within 75 min. The direct mass spectrometry specified that the MB solution was degraded by photocatalysis within 75 min.

Solar Induced Photocatalytic Degradation of Methylene Blue by CdS/Ag2O Nanocomposites

AbstractPresent investigation reports the synthesis of stable as well as visible‐light active CdS/Ag2O nanocomposite photocatalysts in three varied ratios to be engaged in degradation of methylene blue (MB) dye. As‐synthesized photocatalysts have been characterized with the aid of diverse characterization techniques such as X‐ray diffraction (XRD), FT‐Raman, Fourier transform infrared spectroscopy (FT‐IR), X‐ray photoelectron spectroscopy (XPS), UV‐visible and Photoluminescence (PL) spectroscopy, and transmission electron microscopy (TEM). XRD pattern clearly depicts the presence of hexagonal CdS phase and cubic Ag2O phase. Results show a remarkable enhancement of photocatalytic activity for MB degradation especially for CdS/Ag2O nanocomposite with maximum efficiency up to 88.8 %. Moreover, the effective bandgap of CdS/Ag2O (1 : 2) nanocomposite has been significantly reduced to 1.71 eV from pure CdS (2.15 eV). It can be derived that CdS/Ag2O photocatalysis may be envisaged for treatment of diluted waste water containing organic pollutants.

TiO2/Diazonium/Graphene Oxide Composites: Synthesis and Visible-Light-Driven Photocatalytic Degradation of Methylene Blue

In the present article, the synthesis of TiO2/diazonium/graphene oxide and its photocatalytic activity for methylene blue (MB) degradation have been demonstrated. The functionalization of graphene oxide (GO) with diazonium salt (diazonium-GO) was conducted for enhancing the dispersibility of GO in distilled water. TiO2 was highly dispersed in diazonium-GO to form TiO2/diazonium/graphene. The obtained specimens were characterized by X-ray diffraction, FT-IR spectroscopy, Raman spectroscopy, UV-Vis spectroscopy, scanning electron microscope, transmission electron microscopy, and X-ray photoelectron spectroscopy. It was found that the TiO2 phase in TiO2/diazonium/GO composites can be controlled by adjusting the amount of ethanol or titanium oxide in the reactant mixture. The obtained composites exhibited photocatalytic activities for methylene blue degradation (MB). The composite with ac. 70% anatase can provide the highest MB degradation efficiency. The studying of some intermediates for MB photocatalytic degradation using LC-MS showed that structure of MB by the cleavage and oxidation of one or more of the methyl group substituent on the amine groups lead to form compounds with low molecular masses. Total organic carbon studies confirmed a complete mineralization of MB. The present catalyst was stable and recyclable after three times with a negligible loss of catalytic activity. In addition, the TiO2/diazonium/GO can also photocatalyze for the degradation of some other dyes (phenol, methyl red, and Congo red).

Hydrothermal syntheses, crystal structures, and photocatalytic properties of two Co(II) complexes with the flexible citraconic acid

AbstractTwo Co(II) coordination polymers, [Co(ca)(bib)]n (I) and {[Co(ca)(bibp)1.5]·1.5H2O} n (II) (H2ca = citraconic acid, bib = 1,4‐bis(1‐imidazoly)benzene, bibp = 1,4‐bis‐[4‐(imidazol‐1‐yl)benzyl]piperazine), were prepared by hydrothermal method and measured structurally by single‐crystal X‐ray diffraction, infrared spectroscopy, and elemental analysis. Complex I shows a 2D layer structure containing Co‐carboxylate chains. Complex II displays a 3D metal–organic framework composed of the binuclear [Co2(CO2)2]2+ cluster nodes through ca2− and bibp as linkers with (412·63) topology. Complexes I and II have high thermal stabilities because their frameworks maintain good integrity before 340°C and 265°C, respectively. Both complexes show well photocatalytic activities for methylene blue degradation under UV irradiation in the presence of H2O2, which may be used as potential materials for photocatalytic dyes degradation.

ZnO supported Au/Pd bimetallic nanocomposites for plasmon improved photocatalytic activity for methylene blue degradation under visible light irradiation

Recently, photocatalysis has attracted great attention due to its potential applications in the environmental sector. Visible light driven metal–semiconductor photocatalysts with efficient light absorption, high charge separation, enhanced surface plasmon resonance, and utilized active sites have emerged as promising materials for the degradation of organic pollutants. Here, plasmonic ZnO/Au/Pd nanocomposites, with various concentrations of Au (5, 10, and 15 wt%) and 5 wt% of Pd nanoparticles (NPs) were prepared by a facile and eco–friendly three–step pulsed laser ablation in liquid and photodeposition technique without utilizing any surfactants or capping agents to enhance the photocatalytic performance under visible light illumination. The plasmonic properties of Au NPs and an excellent trapping of photogenerated electrons on the surface of Pd led to the improved photocatalytic activity (PCA). The as-prepared ZnO/Au/Pd nanocomposites were characterized by numerous spectroscopic and microscopic techniques, and the results confirmed the fabrication of Au and Pd NPs homogeneously decorated on the surface of ZnO nanospheres. The effect of plasmon improved photocatalytic activity of the ZnO/Au/Pd photocatalysts was investigated by the degradation of methylene blue dye under visible light illumination. The optimum ZnO/Au/Pd nanocomposite was ca. 5.4 times more efficient at degrading methylene blue than pure ZnO. This exceptional improvement of photocatalytic activity for the ZnO/Au/Pd catalysts was due to the enhanced surface plasmon resonance effect of the Au NPs under visible light illumination, and the deposited Pd NPs assisted as an electron storage chamber for the degradation of methylene blue, thus, enabling the separation of charge carriers. Based on the experimental results, a possible photocatalytic mechanism for the degradation of methylene blue catalyzed by the ZnO/Au/Pd nanocomposite was proposed.

Photocatalytic dye degradation and hydrogen production activity of Ag3PO4/g-C3N4 nanocatalyst

Recently, photocatalysts have received increasing attention owing to their potential to resolve issues regarding the environment and alternative sources of energy. Here, highly effective visible-light-driven organic–inorganic hybrid heterojunction graphitic carbon nitride–silver phosphate nanocomposite (GCN–Ag3PO4 NCs) were synthesized via the hydrothermal method. The synthesized photocatalyst was characterized by X-ray diffraction, Fourier transform infrared, X-ray photoelectron spectroscopy, and UV–Vis diffuse reflectance spectroscopies, scanning electron microscopy and transmission electron microscopy, and subsequently utilized for photocatalytic dye degradation and hydrogen production. The GCN–Ag3PO4 NCs exhibit excellent photocatalytic activity for methylene blue degradation under solar simulator visible light, with a hydrogen production activity higher than that of pristine Ag3PO4. The hydrogen production rate of GCN–Ag3PO4 NCs is 44.5 times higher than that of Ag3PO4. Therefore, GCN–Ag3PO4 NCs are promising as effective photocatalysts for environmental protection.

Visible-Light Photocatalytic Activity of Fe and/or Ni Doped Ilmenite Derived-Titanium Dioxide Nanoparticles.

Pure TiO₂ nanoparticles and ones doped with Fe and/or Ni were successfully prepared by a co-precipitation method from ilmenite. The samples were structurally characterized by XRD, XPS, FT-IR, UV-vis, SEM, EDX, AAS and BET measurement. The XRD results showed that all samples were anatase TiO₂, and no characteristic peaks of dopants were observed. The crystallite sizes of all doped TiO₂ nanoparticles were less than 20 nm and doping TiO₂ with metal ions can suppress the crystal growth of the particles. The XRD and XPS results indicated that TiO₂ was uniformly doped and its crystalline phase was not changed by doping. The specific surface area of Fe-Ni/TiO₂ is bigger than that of the un-doped TiO₂. The pore size and pore volume of Fe-Ni/TiO₂ is smaller than that of the un-doped. UV-vis spectra of the samples showed that the absorption edge red shifted with increasing doped metal content. The photocatalytic activity was evaluated in oxidative degradation of methylene blue (MB) with H₂O₂ under visible light irradiation. When doped with a single type of transition metal, the photocatalytic performance of Ni-doped samples was lower than that of Fe-doped ones. For the co-doped catalysts, the catalytic efficiency of 0.5%Fe₄%Ni/TiO₂ was the highest, reaching 93.34% after 250 min. Metal doping enhanced the photocatalytic decomposition of methylene blue compared with that of pure TiO₂ by up to 1.5 times. The synergistic effects of the two metal ions improved the photocatalytic performance. The particles exhibited pronounced activity in degradation of MB as well as efficient recyclability. The photocatalytic degradation mechanism of methylene blue was analyzed.

Facile synthesis of CeO2-graphene oxide composites with enhanced visible-light photocatalytic performance

A series of CeO2-graphene oxide (CeO2-GO) composites were systematically prepared and compared for the visible-light photocatalytic degradation of methylene blue (MB). The experimental results show that the as-prepared CeO2-GO (5.0 wt%) composite exhibits superior photocatalytic activity as compared to pure CeO2. An optimum weight ratio of GO to CeO2 not only causes a decrease in particle size of CeO2, but also leads to an increase in BET specific surface areas and favors an effective separation of the photogenerated electron-hole pairs, which should be responsible for the enhanced photocatalytic performance. More importantly, there is a direct correlation between the electrocatalytic activity of CeO2-GO and its photocatalytic activity for the visible-light photocatalytic degradation of MB. This fundamental research will provide guideline for exploring of highly efficient photocatalysts with many potential applications in future.