Brauner-Emmett-Teller Research Articles

Facile and innovation synthesis of Zn-Mn-Co-LDH/polypyrrole and its application in investigating ethanol oxidation in an alkaline medium

Overvoltage and low current are observed for ethanol electrooxidation on the surface of many unmodified electrodes. Therefore, it is desirable to use a suitable catalyst for ethanol electrooxidation to increase the current. This research introduces a new sensor to catalyze ethanol oxidation in an alkaline environment. This new Zn-Mn-Co LDH/PolyPyrrole/GCE nanocomposite sensor exhibits high catalytic activity for ethanol electrooxidation. It changes the oxidation potential of ethanol to a less positive potential. To identify this proposed sensor, X-ray diffraction (XRD), Brauner Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), FT-IR spectroscopy, field emission scanning electron microscopy (FESEM), thermal analysis (TGA), high-resolution transmission electron microscopy (HR-TEM) and cyclic voltammetry techniques were used. Ethanol electrooxidation was investigated by cyclic voltammetry technique. The effects of scan rate and ethanol concentration on the ethanol oxidation peak have been investigated. The proposed sensor showed long-term stability. This prepared nanocomposite can be used as an anode catalyst for ethanol fuel cells.

Croconic Acid Integrated Zwitterionic Conjugated Porous Polymer for Effective Iodine Adsorption.

Given the rapid growth of the nuclear sector, effective treatment of radioactive iodine is critical. Herein, we report the synthesis and the iodine adsorption properties of croconic acid (CTPB) and squaric acid (STPB) containing π-conjugated novel zwitterionic conjugated porous polymers (CPPs). The CPPs have been synthesized through a condensation reaction of tris(4-aminophenyl)benzene with croconic acid or squaric acid in high yields (~95%). The ionic nature of the polymers promoted high iodine/polyiodide vapour adsorption capacity of up to 4.6 g/g for CTPB and 3.5 g/g for STPB under ambient pressure at 80 °C. The zwitterionic framework (croconic acid or squaric acid units) coupled with the aromatic units is expected to effectively capture molecular iodine (I2) and polyiodides (I3- and I5-). The iodine adsorption properties of the polymers have been studied using Fourier-Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Brauner-Emmett-Teller (BET) analysis, and Raman Spectroscopy. Besides this work, there are only three ionic units for effective iodine adsorption. This work demonstrates the importance of zwitterionic units in the porous network reported for iodine adsorption and separation.

TiO2 nanoparticle seeds transformed into nanotubes for effective dye-sensitized solar cell application

Morphology plays a vital role in dye-sensitized solar cells (DSSCs) due to their high surface area, dye adsorption and electron transport. In this study, we have designed and fabricated titanate nanotube photoanodes by a simple one-step hydrothermal method. High-resolution transmission electron microscope (HRTEM) analysis revealed the transformation of nanoparticles to nanotube morphology. Brauner-Emmett-Teller (BET) method showed the enhanced surface area and pore diameter of nanotubes. TiO2 nanotube photoanode showed excellent energy conversion efficiency (2.38 %), short circuit current densities (Isc) (6.29 mA/cm2), and fill factors (FF) (0.63), respectively.

Multifunctional platform for future applications in cell and tissue engineering based on silicate phosphate hydroxyapatite co-doped with Li+, Eu3+ and Gd3+ ions

Although hydroxyapatite has established itself as a promising biomaterial for the simultaneous diagnosis and treatment of bone defects, several physicochemical properties can be further refined to achieve a specialized theranostic platform for cell and tissue engineering. In this context, we synthesized silicate-substituted hydroxyapatites co-doped with Li+, Eu3+, and Gd3+ ions (abbr. as Si-HAp-LEG) using a microwave-assisted hydrothermal method. The aim was to create a combination of dopants to stimulate bone regeneration (Li+ ion) while enabling bioimaging (Eu3+ and Gd3+ ions). Structural and morphological assessments included, e.g., XRPD (X-ray Powder Diffraction), HR-TEM (High-resolution Transmission Electron Microscopy) imaging, and BET (Brauner-Emmet-Teller) analysis. Unit-cell parameters were estimated via Rietveld refinement. The luminescence properties (emission, excitation spectra, and emission kinetics) were recorded depending on the varying Li+-ion concentration. The cytocompatibility of biomaterials was tested using hBMSCs (multipotent human bone-marrow mesenchymal stromal cells). In vitro assays evaluated biomaterials’ effects on morphology, metabolic activity (Alamar blue assay), and transcriptomic activity (RT-qPCR). The results indicate that co-doping with Li+, Eu3+, and Gd3+ ions introduces distortions while preserving the crystal structure of hydroxyapatite. Additionally, the cells maintained proper morphology and ultrastructure, internalizing biomaterials without significant cytotoxicity. The biomaterials also triggered the expression of key transcriptional factors. Si-HAp-LEG biomaterials, particularly LEG-222 and LEG-221, exhibit desired physicochemical and biological features, rendering them highly bioactive and promising for cell and tissue engineering applications.

Systematic exploration of defect-rich 2D nanopetal assembled 3D ZnO nanoflowers for improved photocurrent generation and photocatalytic performance

Zinc Oxide (ZnO) stands as a highly significant metal oxide semiconductor with a large band gap of (3.2 eV), showcasing multifaceted properties. Significant findings of this study, designate the successful fabrication of 3D nanoflowers (NFs) with a specialized ZnO nanoarchitecture through a facile polyol process, considered by a notable presence of defect sites, as a photocatalyst for the deterioration of Rhodamine B (RhB). All ZnO NFs display increased absorption and a distinctive shift towards longer wavelengths, indicating a red shift phenomenon. Raman scattering, photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), and electron spin resonance (EPR) unveiled that, the ZnO/24 hr, exhibited a notable abundance of defect states. The Brauner–Emmett–Teller (BET) analysis shows surface area of 55.14 m2g−1 for ZnO/24 hr resulted in a subsequent augmentation of the concentration of surface defects potentially enhancing the RhB photodegradation efficiency of 98%, surpassing the performance of other ZnO NFs samples, with a kinetic rate of 0.0638 min–1 under sunlight irradiation and better photocurrent response that improves the photogenerated separation of charge carriers. Hence, the findings from this investigation will offer novel perspectives for enhancing the photocatalytic and photoelectrochemical attributes of ZnO NFs grown over different durations.

Detection of Methicillin-Resistant Staphylococcus Aureus using vancomycin conjugated silica-based fluorescent nanoprobe

Methicillin-Resistant Staphylococcus Aureus (MRSA) is a worldwide major pathogenic bacteria that has emerged over the past three decades as the leading cause of nosocomial and community-acquired infections. Biosensors can provide rapid, sensitive, and selective detection of the presence and number of bacteria in various environments. Herein, a novel fluorescence nanoprobe was designed as a biosensor for MRSA detection using dye-incorporated silica nanoparticles (FSiNP). Based on the results of specific surface area analysis using the Brauner Emmett-Teller (BET) method, the surface area of the nanoparticles was obtained at 377.127 m2/g, and the X-ray diffraction (XRD) analysis confirmed that it was in the amorphous phase. Vancomycin, as the bioreceptor, was immobilized on the silica surface through a hydrosilylation reaction, generating the biosensing platform FSiNP-Van. Each modification step was corroborated by the Fourier Transform Infra-Red (FTIR) spectroscopy. The sensing principle was based on the fluorescence-quenching mechanism of FSiNP-Van at 515 nm obtaining a rapid response time of 20 min. The FSiNP-Van nanoprobe provided a wide linear concentration range of 10–106 CFU/mL with a limit of MRSA detection calculated at 1 CFU/mL. The fluorescent nanoprobe demonstrated here is expected to find applications in point-of-care (POC) diagnostics to detect the presence of MRSA bacteria.

Use of molecular simulation for evaluating adsorption equilibrium of inhalation anaesthetic agents on metal–organic frameworks

AbstractMetal–organic frameworks (MOFs) were studied as alternatives to zeolites and activated carbon for adsorptive removal of wasted inhalation anaesthetic agents (IAA). Monte Carlo simulation was used to predict equilibrium adsorption isotherms of IAA on selected MOFs. Rather than generic forcefields (FFs), the all‐atom FF parameters published by Arcario were used for IAA modelling. Continuous fractional component Monte Carlo (CFCMC) proved crucial for speedy simulation of large molecules. We found that allocating 70% probability to the CFlambdaSwap move gave optimum fits between simulation and experiment. The simulations provided us with an insight into the adsorption mechanisms of IAA in these structures. Heats of adsorption, Brauner‐Emmet‐Teller (BET) surface area, and total pore volume were deduced to be the crucial parameters for low, medium, and high range of relative pressures in the isotherm. Therefore, the chromium atoms in MIL‐101‐Cr are better adsorbers of IAA than MIL‐100‐Al at lower pressures despite the similarities in terms of the type of linkers and topology. Our simulation results corroborated the earlier published studies on the self‐association behaviour of sevoflurane molecules based on the experimental isotherms reported for MOF‐177‐Zn. Finally, the high polarity of IAA is thought to explain good low‐pressure simulation/experiment data agreement for the MOFs possessing coordinatively unsaturated sites (CUS) despite using generic DREIDING FF for the framework atoms. Our in‐house parsing code helped realize that the grand‐canonical Monte‐Carlo simulation speed is not the same for all pressure points but decreases for higher pressure points. This can be explained by increased density of the adsorbates making successful trial moves less probable.

Copper phosphorylated cellulose nanofibers mediated azide-alkyne cycloaddition click reaction in water

Heterogenous copper-catalyzed azide-alkyne cycloaddition reaction (CuAAC) was performed by using the phosphorylated carbohydrate-based cellulose nanofibers loaded with copper(II) ions. The copper-containing phosphorylated cellulose nanofibers (here after noted Cu(II)-PCNFs) were prepared in two different morphologies, namely the paper and foam ones and characterized by different techniques, including Scanning Electronic Microscopy (SEM), Energy Dispersive X-ray (EDX), Brauner-Emmett-Teller (BET), FT-IR spectroscopy (FTIR), Thermal Gravimetric Analysis (TGA), X-ray Photoelectron spectroscopy (XPS) and Atomic Force Microscopy (AFM). Cu(II)-PCNFs showed high activity in the CuAAC reaction when applied to the ligation of various organic azides and terminal alkynes without any reducing agent, resulting in the regioselective synthesis of 1,4-disubstituted-1,2,3-triazoles in water at room temperature. These nanofibers were recovered and reused with no significant loss of catalytic activity or selectivity. A carbohydrate-based bio-support cellulose as reliable heterogenous catalyst was efficiently developed in view of taking the click chemistry concept to sustainable chemistry.

Thermal stability and rheological properties of PMMA/B2O3 nanocomposites synthesised by melting method

ABSTRACT Nano boron oxide (B2O3) was firstly produced from granular B2O3 by ball milling under cryogenic conditions. Then, PMMA/B2O3 nanocomposites were synthesized by melting method and then characterized. Finally, the rheological properties of PMMA/B2O3 nanocomposite were investigated using a high pressure capillary rheometer. Brauner-Emmet-Teller (BET) surface area analysis showed that the surface area of B2O3 increased with cryogenic grinding. Transmission electron microscopy (TEM) images revealed that B2O3 particles were nano-sized. Scanning electron microscopy (SEM) images showed that the morphology changed with the increase of B2O3 amount. The thermal stability of nanocomposites was found to be better than PMMA. PMMA degraded in two steps, while nanocomposites degraded in one step. It was determined that the amount of residue increased with increasing amount of B2O3. Both PMMA and nanocomposites exhibited non-Newtonian shear thinning flow behavior. In addition, rheological data were found to be highly compatible with the Power Law model.

Sunflower waste – manganese iron oxide composite for hazardous dye removal

Sunflower waste (SF), an easily available agricultural waste was used as a primary material in the synthesis of sunflower waste – manganese iron oxide (SF-MIO) composite for the aim of waste recycling and synthesizing new composite material for dye adsorption. The synthesized adsorbent was characterized using various techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric and differential thermal analysis (TG-DTA) and Brauner-Emmett-Teller (BET) analysis. Dye adsorption ability of the SF-MIO composite in the aqueous solution was investigated using the anionic dye Congo Red (CR). Effect of adsorption parameters such as adsorbent dosage, temperature, initial dye concentration and time were investigated. According to the characterization results, manganese iron oxide addition provided porous microstructure to sunflower waste and increased its surface area from 1.1814 to 47.1415 m2/g thus made sunflower waste more suitable for adsorption. Adsorption process was maintained in endothermic nature and maximum adsorption capacity of SF-MIO on to CR was calculated as 45.66 mg/g. Pseudo-first order, pseudo-second order, Elovich kinetic models and Langmuir, Freundlich, Temkin and Halsey isotherms were studied. The adsorption behavior of CR on SF-MIO composite can be well described by Freundlich and Halsey isotherm models (R2=0.996) and pseudo-second order kinetic model (R2=0.999).

Biogenic Silver Kaolinite Nanocomposite for the Sequestration of Lead and Cadmium in Simulated Produced Water

Biologically inspired nanocomposites are currently attracting significant recognition in view of their environmentally friendly, cost efficient and sustainable properties. In this study, silver-kaolinite nanocomposite (SKN) was synthesized using aqueous extracts from fresh leaves of Aloe vera as a bioreducing agent and employed for the removal of lead (Pb) and cadmium (Cd) ions from simulated produced water (SPW). Morphological properties of SKN were examined using transmission electron microscopy (TEM), scanning electron microscopy (SEM), x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy dispersive x-ray (EDX) spectroscopy, Brauner-Emmett-Teller (BET) and ultraviolet-visible (UV-Vis) spectrophotometry with average particle size ranging from 45 to 60 nm. Different physicochemical parameters (initial concentration (10 - 120 mg/L), adsorbent dosage (0.01 - 0.2 g), pH (2 - 8) and contact time (5 - 150 min)) were investigated to ascertain the efficiency of SKN. The results revealed optimum adsorption of 142 and 120 mg/g for lead and cadmium ions respectively at initial metal concentration of 100 mg/L, 0.05 g of SKN dose and pH 6 for 60 min. Freundlich isotherm and pseudo-second order kinetic model adequately interpreted the equilibrium and kinetic data respectively.

Sorption enhanced steam reforming of methane over waste-derived CaO promoted MgNiAl hydrotalcite catalyst for sustainable H2 production

The waste-derived CaO promoted Mg-Ni-Al (MNA) based hydrotalcite hybrid catalysts were synthesized by co-precipitation and wet impregnation method and tested for sorption enhanced steam methane reforming (SESMR) for hydrogen (H2) production. The catalysts were characterized using X-ray diffractometer (XRD), Field emission scanning electron miscroscopy (FESEM), Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, Brauner Emmett teller (BET), laser particle size analyzer, Temperature programmed reduction (TPR), Thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). Various CaO loadings varying from 0% to 15% into the MNA-based hydrotalcite catalysts (MNA HTc) were assessed for SESMR in a fixed bed reactor. The results revealed that 10% CaO@MNA exhibited the best performance in terms of a longer pre-breakthrough period with respect to other compositions. The CH4 fraction, H2 purity, and CO2 production in the absence of CaO were marked at 60%, 55%, and 14% respectively. However, the CH4 fraction and H2 purity increased to 77% and 80%, while CO2 decreased to 3% in the pre-breakthrough period for 10% CaO @ MNA at 650 °C, WHSV 2000 mL CH4 g−1h−1 and S/C of 2.0. The nanocomposite 10%CaO@MNA was tested over three consecutive SESMR cycles at 650 °C to analyze its regeneration capacity. The hybrid catalyst was also tested at various temperatures from 650° to 850°C to investigate the effect of CaO sorbent. It was found that elevated temperatures > 750 °C likely reduced the carbonation reaction and shifted the technique to SMR. The spent catalyst exhibited negligible carbon formation on the catalyst surface. The catalytic performance of the reported catalyst-sorbent system is encouraging for further regeneration studies for SMR and other reforming techniques.

Fabrication and characterization of FITC-modified naturalbased silica nanoparticles using sol-gel method

This research aimed to synthesize fluorescent silica nanoparticles (SiFITC) modified with the fluorescein isothiocyanate (FITC) dye using sol-gel method. The FITC dye was used as the fluorophore to produce fluorescent silica nanoparticles. The precipitate from geothermal power plant containing SiO2 was used as a precursor and added with NaOH at 90°C generating sodium silicate. FITC solution was added with various concentrations ranging from 0.1, 0.2, 1, 5 to 10 mg/mL and the mixture was allowed to age for 18 hours. Characterization of SiFITC was measured using fluorescence spectrophotometer to obtain the fluorescence intensity, Fourier Transform Infra-Red (FT-IR) spectroscopy to determine the functional group of SiFITC, Brauner Emmett-Teller (BET) adsorption method to calculate the specific area of the nanoparticles, and X-ray diffraction (XRD) to analyze the crystallographic phases. Fluorescent intensity showed that SiFITC with 1 mg/mL of FITC had the lowest fluorescence intensity indicating self-quenching mechanism due to the overloading of the dye in the silica matrix. The FT-IR spectra showed vibration at wavenumber of 956 (Si-O); 1073 and 798 (Si-O-Si); 3396 (OH) and 1631 cm−1 (Si-OH). BET analysis showed that the specific surface of the SiFITC 480 m2/g and XRD results showed that the samples were in amorphous phase with uniform pore distribution. The results showed that the FITC-modified silica nanoparticles have great potential for further investigation in biosensing applications, particularly fluorescence or optical based detection of antibiotic resistant bacteria.

Hydrogen photoproduction on TiO2-reduced graphene oxide hybrid materials from water-ethanol mixture

Titanium dioxide mixed with reduced graphene oxide (rGO) has been tested in the photoproduction of hydrogen using UV light from water-ethanol combination in gas phase. The presence of the reduced graphene oxide in TiO2/rGO nanocomposites affects the physicochemical properties of hybrid materials, thus enhancing the photocatalytic activity. The obtained catalysts have been characterized for physical-chemical properties using X-ray diffraction (XRD), UV–vis spectroscopy, Raman spectroscopy, transmission electron microscopy (TEM)/high-resolution transmission electron microscopy (HRTEM), and Brauner Emmett Teller (BET). The best photocatalyst has been obtained by mixing anatase and rGO (10 wt%) after calcination at 700 °C. This TiO2-rGO composite exhibited the highest performance with a hydrogen photogeneration rate of 9.5 mmol h−1 g−1.

Spongy membranes for peroxidase purification from Brassica oleracea roots

In this work, it was aimed to purify peroxidase from Brassica oleracea roots using newly synthesized cryogel membranes. 2-4-vinylphenylboronic acid (VPBA) containing 2-hydroxyethyl methacrylate (HEMA) [PHEMABA] cryogel membranes were prepared successfully and swelling tests, scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, contact angle measurements, and Brauner-Emmet-Teller (BET) surface area analysis were done for characterization. Effect of experimental conditions on peroxidase binding capacity of PHEMABA cryogel membranes was determined by examining parameters such as pH, temperature and time with binding studies. Maximum peroxidase binding capacity of PHEMABA cryogel membranes was determined as 22.01 mg/g for 2 mg/mL equilibrium peroxidase concentration at pH 8.0. Finally, peroxidase was purified from Brassica oleracea roots with 85.38% yield and 18.38 purification fold. According to obtained results, spongy PHEMABA cryogel membranes show high peroxidase binding capacity and could be suggested as a boronate affinity model system for enzyme purification.

The Effect of Rhodamine B on The Properties of Fluorescent Nanoparticles Derived from Geothermal Silica

Rhodamine B can be used as a fluorophore to produce fluorescent silica nanoparticles derived from geothermal sludge. The purpose of this research is to synthesize fluorescent silica nanoparticles (FSNP) modified with rhodamine B and cetyl trimethyl ammonium bromide (CTAB) using sol-gel method. Geothermal waste was used as a precursor and added with NaOH at 900C to generate sodium silicate. Rhodamine B, as the fluorescent dye were added with concentration variations ranging from 0.156 mg/g to 10 mg/g.CTAB was used as template and HCl 2N was applied as gelling catalyst with aging time of 18 hours. Characterization of FSNP was measured using spectrofluorometer to identify the fluorescent intensity, fourier transform infrared (FT-IR) to determine the functional group of FSNP, Brauner-Emmett-Teller (BET) adsorption to calculate the specific area of the particles, X-ray diffraction (XRD) to analyze the crystallographic phases, and transmission electron microscopy (TEM) to analyze the surface morphology of the FSNP. FT-IR and fluorescent intensity results showed that FSNP with 2.5 mg/g of rhodamine B had the optimum characteristics. The FSNP was in amorphous phase with uniform pore distribution. BET analysis showed that the specific surface of the FSNP was 190.22 m2/g.

Determination of micropore volumes of ZSM-5 zeolite samples by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy using back-propagation artificial neural network (BP-ANN) and non-negative matrix factorization -alternating least squares (NMF-ALS) as chemometric approaches

In this paper, the proposed method has been introduced for qualitative and quantitative determination of micropore volume in nano ZSM-5 zeolite samples based on diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy along with chemometric methods.For this purpose, a total of 72 samples were provided and DR-FTMIR spectra corresponding to the samples were obtained in the range of 400–4000 cm−1. In order to estimate total surface area from a nitrogen adsorption isotherm, Brauner Emmett Teller (BET) method as a reference method was used.The results are displayed that the significant adsorption peak of the mid-IR spectroscopy in 3660 cm−1 is corresponded to the SiOH groups of the zeolite external surface that is a criterion for the intensity of the mesoporosity. The intensity of the 3745 cm−1 peak is grown up with enhancing the external surface area.These changes were evaluated by non-negative matrix factorization -alternating least squares (NMF –ALS) chemometrics approach for estimating the microporosity in nano ZSM-5 zeolite samples.Back-propagation artificial neural network (BP-ANN) as a nonlinear multivariate regression technique was also used to determine the micropore volume of zeolites based on DRIFT spectroscopy.For BP-ANN model in these samples, R and minimum mean squared error (MSE) values of the testing set data with 5 hidden nodes were 9.95 × 10−1 and 4.11 × 10−7, respectively.The achieved results are presented that DRIFT spectroscopy coupled with chemometrics approaches is a precise, explicit and easy technique to analyze the volume of the micropore in ZSM-5 nano-catalyst samples.

One-Pot Synthesis of Sulfur-Doped TiO2/Reduced Graphene Oxide Composite (S-TiO2/rGO) With Improved Photocatalytic Activity for the Removal of Diclofenac From Water.

Sulfur-doped TiO2 (S-TiO2) composites with reduced graphene oxide (rGO), wt. % of rGO equal to 0.5%, 2.75%, and 5.0%, were prepared by a one-pot solvothermal procedure. The aim was to improve photocatalytic performance in comparison to TiO2 under simulated solar irradiation for the treatment of diclofenac (DCF) in aqueous medium. The obtained composites were characterized for physical-chemical properties using thermogravimetric analysis (TGA), X-ray diffractograms (XRD), Raman, scanning electron microscopy (SEM)/energy dispersive X-ray (EDX), Brauner Emmett Teller (BET), and photoluminescence (PL) analyses, indicating successful sulfur doping and inclusion of rGO. Sulfur doping and rGO have successfully led to a decrease in photogenerated charge recombination. However, both antagonistic and synergistic effects toward DCF treatment were observed, with the latter being brought forward by higher wt.% rGO. The composite with 5.0 wt.% rGO has shown the highest DCF conversion at pH 4 compared to that obtained by pristine TiO2, despite lower DCF adsorption during the initial dark period. The expected positive effects of both sulfur doping and rGO on charge recombination were found to be limited because of the subpar interphase contact with the composite and incomplete reduction of the GO precursor. Consequent unfavorable interactions between rGO and DCF negatively influenced the activity of the studied S-TiO2/rGO photocatalyst under simulated solar irradiation.

Growth of hierarchical ZnO nano flower on large functionalized rGO sheet for superior photocatalytic mineralization of antibiotic

In this study, reduced graphene oxide supported mesoporous zinc oxide ([email protected]) was synthesized and applied for the photocatalytic mineralization of ofloxacin, an antibiotic, in the aqueous solution. In-situ [email protected] nano-photocatalysts with different rGO content (0.2%, 0.5%, 1% and 2%) were synthesized using a reflux column method. The nano-photocatalyst was characterized by its structural (crystallinity), morphological, as well as optical properties with the help of powdered X-ray diffraction (P-XRD), field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Raman spectroscopy, Brauner Emmet Teller (BET), thermo-gravimetric/differential thermal analysis (TGA/DTA) and UV–vis diffuse reflectance spectroscopy (DRS). The influences of pH (5–9) and catalyst dose (400–1400 mg/dm3) with irradiation time were studied. At optimum conditions (0.5% [email protected] dose of 1200 mg/dm3 for ofloxacin, pH = 7, and time = 300 min), ultimate degradation efficiency was found to be ≈99%, under UV light irradiation. The degradation kinetics fitted well with the first-order kinetic model. The photocatalytic mechanism of the enhanced photo-degradation in the presence of rGO was studied by comparing band structure with the potentials of the main reactive species (O2− and OH), which result in the mineralization of ofloxacin. The intermediates and pathways during the mineralization were determined using liquid chromatography, which is coupled with mass spectrometry (LC–MS) analysis and a possible pathway was also proposed on the basis of identified intermediates.

Photocatalytic activity of solvothermal prepared BiOClBr with imidazolium ionic liquids as a halogen sources in cytostatic drugs removal

In this work, the BiOClBr, as a new family of bismuth based semiconductors, was successfully applied to remove of cytostatic drugs from water under UV-Vis light irradiation. BiOCl, BiOBr and BiOClBr were synthesized using two steps solvothermal method in glycerol. The inorganic salts (KCl and KBr) and 1-butyl-3-metylimidazolium chloride (BmimCl) and 1-butyl-3-metylimidazolium bromide (BmimBr) ionic liquids (ILs) were used as the source of halides for the photocatalysts synthesis. The as-fabricated samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and UV–vis diffuse reflectance spectroscopy (DRS). The specific surface area was measured by Brauner-Emmett-Teller (BET) technique. Additionally, Fourier-transform infrared spectroscopy was used to evaluate the presence of IL on the photocatalysts surface. The comparison of photocatalytic activity between BiOCl and BiOClBr photocatalysts towards 5-fluorouracil (5-FU), imatinib (IMA) and cyclophosphamide (CP) removal was conducted. The highest photocatalytic activity in the cytostatic drugs degradation and mineralization was found using BiOClBr IL synthetized via ILs as the halogens source. The study showed that BiOClBr IL synthesized in the presence of ILs can be a promising material in the water decontamination methods.