Ultraviolet Diffuse Reflectance Spectroscopy Research Articles

Synergistic Effect of NiAl-Layered Double Hydroxide and Cu-MOF for the Enhanced Photocatalytic Degradation of Methyl Orange and Antibacterial Properties

This study synthesized NiAl-layered double hydroxide (LDH)/Cu-MOF photocatalyst using a simple impregnation method involving NiAl-LDH and Cu-MOF. The successful synthesis was confirmed through Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), zeta potential measurements, thermogravimetric analysis (TGA), ultraviolet diffuse reflectance spectroscopy (UV-DRS), N2 adsorption at −196 °C, and electrochemical impedance spectroscopy (EIS). Photocatalysts based on NiAl-LDH, Cu-MOF, and NiAl-LDH/Cu-MOF were used to remove methyl orange (MO) dye from contaminated water. The impact of various factors, including pH, dye concentration, and photocatalyst amount, on MO degradation efficiency was assessed. FTIR analysis was conducted both before and after dye degradation. The optimal degradation conditions were a photocatalyst dose of 25 mg and a pH of 3. Kinetic studies indicated that the degradation of MO dye onto NiAl-LDH/Cu-MOF followed a pseudo-first-order and an L–H or Langmuir–Hinshelwood model. The value of R2 = 0.94 confirms the validity of pseudo-first-order and Langmuir–Hinshelwood (L–H) kinetic models for the photocatalytic degradation of MO dye. This study highlights the importance of developing novel photocatalysts with improved degradation efficiency to protect the water environment. Antibacterial activity was also performed with antibacterial sensibility testing by disk diffusion to determine minimal inhibitory and bactericidal concentrations. In short, NiAl-LDH/Cu-MOF can be helpful for various biomedical and industrial applications.

Photocatalyst immobilisation on cylindrical surface: Scale-up potential of continuous photocatalytic reactor

The use of continuous photocatalytic reactor is important for sustainable water treatment technology. Photocatalyst immobilisation on supports (of varying shapes and sizes) having the desired degree of uniformity and smoothness is challenging, and is evolving. The major concerns are the geometry of the surface (which restricts the scalability of such systems) and the appropriate adhesion of the photocatalyst. Flat surface has an inherent limitation of low photocatalyst area per floor space, and poor light distribution, whereas cylindrical surfaces can overcome all these limitations. In this work, we have developed and assessed the photocatalyst coating methodology over cylindrical (quartz) surface and have prepared a modular (continuous) photocatalytic reactor. We have immobilised titanium-dioxide on the outer surface of a cylindrical quartz tube using a rotating (coating) mechanism, using the viscous sol prepared from the sol-gel method followed by heat treatment, and not with any binder to the as-synthesized powder. Various characterization techniques, including ultraviolet-diffuse reflectance spectroscopy, energy-dispersive spectroscopy, x-ray diffraction, field-emission scanning electron microscopy, optical surface profilometry, and ultraviolet–visible spectroscopy, are used to evaluate the impact of process conditions – number of layers, rotational speed, and sol viscosity, on the coating uniformity, smoothness, and layer thickness. The performance of the custom-made (modular-type) reactor is evaluated for degradation of the model molecule (pollutant). The reactor performance and capacity can be easily scaled up by parallel connections or introducing multiple coated tubes (to increase the photocatalyst area). The outcome of the work will be of immense value in scaling up the continuous large scale photocatalytic operation and treatment process.

Spectroscopic Characterization of Ti Sites in MWW Zeolite in Presence of Hydrogen Peroxide

AbstractTi‐MWW zeolite is a promising catalyst for partial oxidation reactions. In the present work, a Ti‐MWW sample with high TiO2 loading was synthesized. It was revealed that the Ti insertion in the purely siliceous MWW framework mainly occurs during the post treatment washing with HNO3, when the double structure directing agent synthetic method is used. By exploiting carbon monoxide, acetonitrile, pyridine and ammonia as probe molecules in infrared spectroscopy and diffuse reflectance ultraviolet spectroscopy, the acidic behavior of the Ti sites and the interaction of the Ti sites with hydrogen peroxide (H2O2) were revealed. The Ti Lewis acid sites showed stronger acidity than the one observed in Titanium Silicalite‐1 (TS‐1), with MFI framework. This is coherent with previously reported results, suggesting that a significative fraction of the Ti sites in Ti‐MWW are TiOH(SiO)3 instead of Ti(OSi)4. The Ti‐peroxo and ‐hydroperoxo complexes formed upon H2O2 were shown to be more labile than in TS‐1 and they were shown to be completely reversible upon calcination.

CeO2 nanospheres incorporated with Bi2MoO6/g-C3N4 enhanced photocatalysis towards environmental pollutant Rhodamine B removal.

We have adopted a novel CeO2/Bi2MoO6/g-C3N4-based ternary nanocomposite that was synthesized via hydrothermal technique. The physiochemical characterization of as-prepared samples was examined through various analytical techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy TEM, photoluminescent spectra (PL), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), and ultraviolet diffuse reflectance spectroscopy (UV-DRS) technique. In addition, the photocatalytic performance was carried out by degradation of Rhodamine B dye under visible light irradiation using this nanocatalyst. The ternary nanocomposite achieved 94% of the degradation efficiency within 100min which is higher than the pristine and binary composites under the predetermined condition pH = 7, Rhodamine B dye = 5mg/L, and catalyst concentration = 150mg/L. The experimental synergetic effect of CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite has been ascribed to the interfacial charge carrier migration between CeO2, Bi2MoO6, and g-C3N4. The optical absorption range of CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite was enhanced, and the band gap was reduced up to 2.2eV. In addition, scavenger trapping experiment proves that the super oxide anions (O2-.) and photogenerated holes are the major active species. The reusability and stability experiment proved the CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite keeps good durability during the photocatalytic degradation process after the five successive cycles. Furthermore, based on the results, the charge carrier transfer photocatalytic mechanism was also discussed. This CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite may offer the cheapest material and extend the great opportunity for clean and environmental remediation approach under the visible light irradiation.

Sonophotocatalytic degradation of sulfamethoxazole using lanthanum ferrite perovskite oxide anchored on an ultrasonically exfoliated porous graphitic carbon nitride nanosheet.

The lanthanum ferrite perovskite (La0.8FO) was synthesized using a citric combustion route and then modified with a porous graphitic nitride nanosheet via the wet impregnation-assisted ultrasonic method to produce La0.8FO@PgNS. Various techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, X-ray photoelectron spectroscopy (XPS), ultraviolet diffuse reflectance spectroscopy (UV-DRS), and Tauc plot analysis were employed to confirm the functional moieties, crystallinity, phase change, morphology, composition, and bandgap of La.0.8FO and La0.8FO@PgNS. La0.8FO and La0.8FO@PgNS were used for the sonophotocatalytic oxidative degradation of sulfamethoxazole (SMX) under low energy and ultrasound wave frequency in the presence of visible light. La0.8FO and La0.8FO@PgNS exhibited a sonophotocatalytic degradation capacity of 52.06 and 99.60%, respectively. Furthermore, the rate constant at the optimum condition of pH 7 and 5 mg L-1 concentration was 0.01343 and 0.01494 min-1 for La0.8FO and La0.8FO@PgNS, respectively. The integration of sonolysis and photocatalysis in the remediation process of SMX resulted in a synergy of 2.5-fold. Ultrasonic waves and hydroxyl and superoxide radicals are the main species governing the degradation process while La0.8FO@PgNS was stable over 8 cycles, proving to be a sustainable material for environmental remediation.

Degradation of organic Pollutant by Using of BiVO4-NiFe2O4 Heterostructure Photocatalyst under Visible Light Irradiation: Assessment of Detoxicity Study Using Cirrhinus mrigala.

The current study mainly concentrates on the photocatalytic activity of composite nanomaterial of BiVO4 (BVO), NiFe2O4 (NFO), and BiVO4-NiFe2O4 (BVO-NFO) under visible light. Among these, BVO-NFO composite degrades crystal violet dye within 60 min with a percentage degradation of 95.65% under visible light illumination. The BVO-NFO composite exhibits better photodegradation performance, which can be attributed to the effective light absorption and reduced recombination of the photoexcited charge carriers. Additionally, by applying a magnetic field, the BVO-NFO composite can be magnetically recovered by using the magnet for subsequent recycling. The synthesized composite was characterized using optical techniques like X-ray diffraction, ultraviolet diffuse reflectance spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller, and energy dispersive X-ray analysis. The effect of dye, before and after degradation, on vital organs of fish species was examined such as fish gill (pulmonary-toxicity), fish liver (hepato-toxicity), fish kidney (renal toxicity), fish brain (neural toxicity), and fish muscle (myopathy). This work offers a clear and practical method for designing a highly crystalline semiconductor photocatalyst for dye degradation and the remediation of industrial wastewater.

Influence of Nd3+ ions modified CoAl2O4 nanomaterials for high efficiency dye degradation application

This study aims to elucidate the possible application of cobalt aluminate nanoparticles (CoAl2O4) as a photocatalyst for the removal of organic dyes. The sol-gel method was employed to synthesise Ndx/CoAl2O4 nanoparticles with varying weight percentages (x = 0.0, 0.2, 0.4, and 0.6 wt %). The experimental investigation focused on the photocatalytic destruction of colour, employing a visible light irradiation source. The structural and optical properties of the synthesised nanoparticle were examined through various analytical techniques, including X-Ray Diffraction (XRD), Ultra Violet-Diffuse Reflectance Spectroscopy (UV-DRS), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX), Tunnelling Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS). The cubic spinel structure was confirmed through the study of the X-ray diffraction (XRD) pattern of the Ndx/CoAl2O4 nanoparticles. For the compositions x = 0.0, 0.2, 0.4, and 0.6, the nanoparticles exhibited average crystallite sizes of 23.73, 22.99, 21.69, and 21.65 nm, respectively. The synthesised nanoparticle exhibited heterogeneous photocatalytic potential when employed as a model pollutant for the oxidative destruction of crystal violet dye. The experimental findings validated that the CoAl2O4 nanoparticle exhibited a dye degradation rate of 64 % during a 100-min timeframe. Additionally, the 0.6 wt % Nd CoAl2O4 nanoparticle shows a quick dye degradation rate of 91 % for crystal violet dyes when exposed to visible light sources. Hence, the synthesised nanoparticle exhibits catalytic activity and holds potential for utilisation in the treatment of hazardous contaminants in industrial wastewater.

Exploring structural and optical properties of shock wave-loaded polycrystalline picric acid: implications for molecular engineering applications

Abstract The shock wave impact on hydrogen-bonded organic materials’ structural properties and their responses with respect to their associated functional properties is one of the most prevalent research topics because of the possible emergence of unusual functional properties. Presently, we intend to examine the structural response of the poly-crystalline picric acid samples under shocked conditions. The crystallographic structural responses and the linear optical properties of the test samples have been examined by powder XRD analysis, ultra-violet diffused reflectance spectroscopy (UV-DRS) and Raman spectroscopy, respectively. Under shocked conditions, a considerable modification in the diffraction peak positions and their intensity changes could be witnessed. Notably, linear optical transmittance profiles show remarkable changes according to the number of applied shock pulses, such that the 150-shocked sample has the highest optical transmittance of 53.9 % at 350 nm, whereas the control sample has an optical transmittance of 6.6 %. The Raman spectrum shows the vibrational groups of material that are stable in shocked conditions with similar intensity changes. Based on the obtained XRD, UV-DRS and Raman results, shock wave-induced picric acid samples have remarkably improved characteristics of optical transmittance, which is highly favorable for non-linear optical applications.

Selective C-H Bond Activation in Propane with Molecular Oxygen over Cu(I)-ZSM-5 at Ambient Conditions.

Selective activation of C-H bonds in light alkanes under mild conditions is challenging but holds the promise of efficient upgrading of abundant hydrocarbons. In this work, we report the conversion of propane to propylene with ∼95% selectivity on Cu(I)-ZSM-5 with O2 at room temperature and pressure. The intraporous Cu(I) species was oxidized to Cu(II) during the reaction but could be regenerated with H2 at 220 °C. Diffuse reflectance ultraviolet spectroscopy indicated the presence of both Cu+-O2 and Cu2(μ-O2)2+ species in the zeolite pores during the reaction, and electron paramagnetic resonance results showed that propane activation occurred via a radical-mediated pathway distinct from that with H2O2 as the oxidant. Correlation between spectroscopic and reactivity results on Cu(I)-ZSM-5 with different Cu loadings suggests that the isolated intraporous Cu(I) species is the main active species in propane activation.

Supernanoporous SnO2 particles and spheres as sustainable solar cell constituents

This study presents the synthesis and a comparative report of the properties of supernanoporous SnO2 particles SNSP (0D) supernanoporous SnO2 spheres SNSS (3D) formed with an assembly of SNSP with a view to examine their application as effectual photoanodes in sustainable solar energy conversion. Porosity imposed nanoparticles with extended surface area improve photon interaction and charge transfer by increasing the absorption of light, hence addressing the existing efficiency hurdles in solar cells. SNSP with particle size of ∼23 nm and SNSS with particle size and sphere size of ∼26 nm and ∼800 nm, respectively, were synthesized by treating SnCl4 via solvothermal process at different experimental conditions. Important aspects of the as-synthesized SNSP and SNSS samples, such as the crystal structure, particle size, optical behaviour, identification of elements present, were characterized by powder X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Ultra Violet Diffuse Reflectance Spectroscopy (UV-DRS) and Energy Dispersive Analysis X-ray (EDAX) Spectroscopy techniques. Field dependent dark and photoconductivity studies reveal significant rise in the photoconducting nature, opto-electrical and surface properties of SNSP and SNSS. Pore size distribution and specific surface area of SnO2 particles and spheres were measured by Brunauer-Emmett-Teller (BET) analysis. High Resolution Transmission Electron Microscopy (HRTEM) is performed to analyze the size and shape of the porous SnO2 particles and spheres and further to correlate the data derived from FESEM. From other prevailing applications of porosity imposed nanomaterials such as gas sensing, catalytic and photodegradation the innovation of this work is to depict the novelty of porous SnO2 particle and sphere with highlighting thermal stability to instigate into the charge transport property suitable for solar cell application. The results were analyzed evincing the photovoltaic properties of spheres over particles and hence the PSC constituent among SNSP and SNSS with better proficiency was identified as appropriate photoconducting medium for fabrication of sustainable photovoltaic cells.

Preparation of β-cyclodextrin derivatives/metamizole inclusion complex nanofibers: Characterization, drug release, and wound scratch assay

Nanofibrous wound dressings fabricated by electrospinning have attracted significant research interest as they enable the controlled release of active substances at the wound site. The development of electrospun nanofibers with anti-inflammatory drugs, which demonstrate great potential for wound healing applications, is one of the main focuses of present research efforts. In this study, nanofibrous webs of 2-hydroxypropyl-β-cyclodextrin (HPβCD) and methyl-β-cyclodextrin (MβCD) loaded with metamizole (MMS) were fabricated by electrospinning. The prepared nanofibers were characterized by field-emission scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetric/differential thermal analysis, 1H nuclear magnetic resonance spectroscopy, ultraviolet diffuse reflectance spectroscopy, and photoluminescence analysis. The interactions of HPβCD and MβCD with MMS in aqueous solutions were studied using absorption and fluorescence spectroscopy, and the 1:1 MMS/CD inclusion complexes were theoretically analyzed at the PM3 level of theory. Furthermore, the drug release, biocompatibility, and wound scratch assay of the nanofibers were evaluated. In vitro drug release analysis revealed controllable release of MMS from the nanofibers. The CD nanofibers loaded with MMS showed good biocompatibility with skin fibroblasts. An in vitro wound scratch assay indicated that the nanofibers promoted fast wound closure with a rate of 98.66 ± 3.9%. In summary, the prepared nanofibrous webs are promising candidates for wound-dressing applications.

Plasma electrolytic formation and characterization of MnWO4/WO3 film heterostructures

MnWO4/WO3 p-n heterojunction films were fabricated using a one-step method consisting of the plasma electrolytic oxidation (PEO) of titanium in homogeneous electrolytes containing paratungstate ions and stable water-soluble EDTA-chelated manganese. The influences of the formation current density and W:Mn molar ratio of the electrolyte, which was varied from 1:2 to 2:1, on the composition, morphology, and optical and photocatalytic properties of the resulting coatings were studied. X-ray diffraction analysis, scanning electron microscopy, energy dispersive X-ray analysis, Raman spectroscopy, and ultraviolet diffuse reflectance spectroscopy were used to characterize the formed composites. Regardless of the W:Mn ratio of the electrolyte, the coatings contained crystalline t-WO3 and m-MnWO4. Depending on the formation conditions, the optical band gap energies of the composites varied from 2.63 to 3.01 eV. The largest absorption red shift and lowest band gap energy were observed in the film composite formed in an electrolyte with W:Mn = 2:1, at a current density of 0.2 A cm−2. Composites obtained in electrolytes with W:Mn ratios of 2:1 and 1:1 exhibited photocatalytic activity in the degradation of rhodamine C and methyl orange dyes in the presence of 10 mmol L–1 H2O2 under ultraviolet and visible light irradiation. The role of hydrogen peroxide in this dye degradation on PEO-coated composites under light irradiation is discussed.

Growth optimization, optical, and dielectric properties of heteroepitaxially grown ultrawide-bandgap ZnGa2O4 (111) thin film

Ultrawide bandgap ZnGa2O4 (ZGO) thin films were grown on sapphire (0001) substrates at various growth temperatures with a perspective to investigate the electrical and optical characteristics required for high-power electronic applications. Due to the variation in the vapor pressure of Zn and Ga, severe loss of Zn was observed during pulsed laser deposition, which was solved by using a zinc-rich Zn0.98Ga0.02O target. A pure phase single-crystalline ZGO thin film was obtained at a deposition temperature of 750 °C and an oxygen pressure of 1 × 10−2 Torr. The out-of-plane epitaxial relationship between the sapphire and ZGO thin film was obtained from φ-scan. The x-ray rocking curve of the ZGO thin film grown at 750 °C exhibits a full width at half maximum of ∼0.098°, which indicates a good crystalline phase and quality of the thin film. Core-level x-ray photoelectron spectroscopy of ZGO grown at 750 °C indicated that Zn and Ga were in the 2+ and 3+ oxidation states, respectively, and the atomic ratio of Zn/Ga was estimated to be ∼0.48 from the fitted values of Zn-2p3/2 and Ga-2p3/2. The high-resolution transmission electron microscopy images revealed a sharp interface with the thickness of the ZGO film of ∼265 nm, and the signature of minor secondary phases was observed. The bandgap of the ZGO film at different growth temperatures was calculated from the ultraviolet-diffuse reflectance spectroscopy spectra, and its value was obtained to be ∼5.08 eV for the 750 °C grown sample. The refractive index (n) and the extinction coefficient (k) were determined to be ∼1.94 and 0.023 from the ellipsometric data, respectively, and the real dielectric function (ɛr) was estimated to be ∼6.8 at energy 5 eV. The ultrawide bandgap and dielectric function of ZGO recommend its possible potential applications in deep-ultraviolet optoelectronic devices and high-power electronics.

Pioneering superior efficiency in Methylene blue and Rhodamine b dye degradation under solar light irradiation using CeO2/Co3O4/g-C3N4 ternary photocatalysts

In this research work, we have successfully synthesized the CeO2/Co3O4/g-C3N4 ternary nanocomposite for hydrothermal method for photocatalytic applications. The synthesized nanocomposites were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy TEM, Photoluminescent spectra (PL), X-ray photoelectron spectroscopy (XPS), Brunauer- Emmett-Teller (BET) and Ultraviolet diffuse reflectance spectroscopy (UV-DRS) technique. As per the optical spectroscopic investigations CeO2/Co3O4/g-C3N4 ternary nanocomposite exhibited the high optical absorption range and its band gap is reduced from 2.95 eV to1.83 eV. The PL spectra showed the lowered emission peak intensity of ternary nanocomposite which is revealed that the better charge separation and slow recombination of electron hole pairs. The highest photocatalytic degradation efficiency of CeO2/Co3O4/g-C3N4 ternary nanocomposite showed 93 % and 86 % towards the pollutant methylene blue and Rhodamine B. Moreover, photodegradation of the pollutants followed pseudo-first order kinetics with a very high-rate constant of 0.02211 min−1 and 0.017756 min−1. Additionally, the ternary nano catalyst was delivered the remarkable stability performance even after five cycles. This research may provide a low-cost approach for synthesized visible light responsive catalysts for use in environmental remediation applications.

Green synthesis, characterization, and application of iron and molybdenum nanoparticles and their composites for enhancing the growth of Solanum lycopersicum

Abstract Nanomaterials have become integral in various aspects of agricultural practices, including the development of nano-fertilizers for optimized crop nutrition. This study explores the application of green-synthesized iron (Fe) and molybdenum (Mo) nanoparticles, as well as their composites, using a guava leaf extract (GLE). The focus is on assessing their impact on nitrogen fixation and growth in tomato plants (Solanum lycopersicum). The nanoparticles were characterized through Fourier Transform Infrared Spectroscopy, Ultraviolet Diffused Reflectance Spectroscopy, Raman Spectroscopy, and X-ray diffraction analysis. The experiment involved two application methods (soil and direct plant spraying) with varying nanoparticle concentrations. Results indicate that the 1% composite nanoparticles applied to the soil and 3% Mo directly on plants yield the most favorable growth and nitrogen uptake in S. lycopersicum. Notably, the 1% composite treatment demonstrated significant enhancement in shoot length, number of branches, and shoot diameter at all three growth stages. Conversely, the 3% Mo treatment when applied directly to plants exhibited optimal results showing substantial shoot length, number of branches, and shoot diameter. Post-experimental soil nutrient analysis further revealed the nuanced effects of nanoparticle applications with 1% composite treatments enhancing nutrient availability compared to control and other concentrations. This research contributes to the evolving field of agri-nanotechnology emphasizing the importance of nanoparticle concentration and application method in influencing plant development and nutrient uptake, paving the way for sustainable agricultural practices.

Photocatalytic Degradation of Ofloxacin in Wastewater Using Mg‐Ni Co‐doped TiO2 Catalyst

AbstractThis study focuses on the preparation and characterization of Mg‐Ni co‐doped TiO2 and its application in the degradation of the pharmaceutical ofloxacin (OFX) under solar irradiation. A wet impregnation method was used to prepare Mg‐Ni co‐doped TiO2. Characterization, optimization, and kinetic studies revealed that the doped TiO2 material is effective in degrading OFX, with potential applications in water treatment or environmental remediation processes. Ultraviolet diffuse reflectance spectroscopy indicated that the band gap of TiO2 was reduced due to doping with Mg and Ni. A reduced band gap can enhance the material's photocatalytic properties, which is important for its application in solar‐driven degradation processes. The catalyst dose and OFX concentration for the degradation process were optimized. A catalyst dose of 2 g L−1 and an OFX solution with a concentration of 40 ppm, maintained at pH 5, resulted in the highest degradation efficiency. The degradation process followed first‐order kinetics, suggesting that the rate of degradation increased with increasing doping.

Improved photocatalytic efficiency of rare earth metal-incorporated magnesium oxide nano-hexagonal sheets for the degradation of Ciprofloxacin and Methylene Blue dye under visible light irradiation

Researchers worldwide are working hard to develop nanoparticles that can be used for the photocatalytic degradation of dangerous substances and antibiotics. In this report, we present a study on how to make yttrium-incorporated magnesium oxide nanoparticles using hydrothermal and calcination methods. These particles measure around 50 nm and have excellent photocatalytic properties. We analyzed them using various physiochemical techniques like X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy with EDAX, transmission electron microscopy, X-ray photoelectron spectroscopy, and ultra-violet diffused reflectance spectroscopy. The nanohexagons created in this study showed reduced band gap energy from 4.8 eV to 3.8 eV when yttrium was incorporated into MgO nanohexagons resulting in an unusual increase in light absorption within the visible light region. Experimental reports show these synthesized nanoparticles could degrade about 66.5 % antibiotic Ciprofloxacin (CIP) and 79 % Methylene Blue (MB) dye respectively with .O2– playing a significant role at every step during the degradation process. This study demonstrates that these synthesized nanohexagons have practical applications as promising photocatalysts for treating toxic contaminants found in industrial effluents.

Novel MgO and Ag/MgO nanoparticles green-synthesis for antibacterial and photocatalytic applications: A kinetics-mechanism & recyclability

The present study identifies the novel nano production of MgO nanoparticles as well as the Ag decoration of MgO nanoparticles using Morinda tinctoria plant extract. Green compounds are used to reduce zero valent atoms and to decorate metal oxide surfaces. X-ray Diffractometer analysis (XRD) was used to examine the cubic structure of MgO (28 nm) and Ag/MgO (21 nm) nanoparticles. Fourier transform infrared spectroscopy (FTIR) analysis was used to determine the reactive functional groups, metal–oxygen bonding, and OH molecules. Ultra-Violet Diffuse Reflectance Spectroscopy (UV-DRS) analysis revealed the optical entity and their orbital electron shift. Using the Kubelka-Munk relation, the optical defect of MgO (4.68 eV) and Ag/MgO (3.18 eV) nanoparticles was calculated. Scanning Electron Microscope (SEM) indicated surface decorations and their pure MgO nanoparticles rod-like shape, and Energy-Dispersive X-Ray Spectroscopy (EDX) identified their elements. TEM analysis confirmed the poly-dispersive nature of the Ag decorations on the MgO surface. X-Ray Photoelectron Spectroscopy (XPS) was used to determine the valency of metal (Ag-3d) and metal oxide (Mg-2 s&O-1 s). MgO and Ag/MgO were used in visible light photocatalytic dye degradation of Rh-B dye. The biological properties were tested against S.aureus and E.coli. The plasmonic decoration on the MgO surface accelerated photodegradation and increased biological susceptibility. The innovative characteristics of this work squeeze the green synthesis of Ag/MgO nanoparticles, their improved photocatalytic and antibacterial performance, and their potential applications in water remediation and biomedicine.

Polymerizable sol–gel synthesis of dark-visible light antibacterial magnetically-recoverable AgBr-loaded iron oxide/alumina nanocomposite

The demand for a facile approach for synthesizing multifunctional nanocomposites is increasingly vital across diverse applications. In this study, a polymerizable sol–gel synthesis has been reported to obtain nanocomposites of magnetic iron oxide deposited over alumina nanopowder. The synthesis is mediated by the deposition of a calculated amount of iron(III) methacrylate, along with ethylene glycol dimethacrylate crosslinker, over alumina nanopowder, followed by thermally-inducing free radical polymerization at 125 °C for 30 min. The powder thus obtained has been subjected to calcination at 400 °C for 150 min and the resultant nanocomposites were characterized using wide-angle x-ray scattering, attenuated total reflectance—Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, field-emission scanning electron microscopy, ultraviolet-diffuse reflectance spectroscopy, vibrating sample magnetometer and Brunauer–Emmett–Teller surface area measurements. The nanocomposites containing 15 and 20 wt% of iron oxide have been found to exhibit a saturation magnetization (M s) value ranging from 12 to 14 emu g−1. To the nanocomposite containing 20 wt% of iron oxide, 5 wt% of AgBr was loaded through thoroughly mixing a surfactant-based precursor, silver-tetraoctyl ammonium bromide (Ag-TOAB), followed by thermolysis. All the nanocomposites have been studied for their antibacterial activity against a representative gram-negative bacterium, Escherichia coli, under dark and visible light conditions. While a 3 mg ml−1 loading of the AgBr-loaded nanocomposite has exhibited complete clearance of the bacterial growth by 90 min in the dark, a similar activity has been observed in 60 min under light. The study has revealed the multifunctionality and high potential of the AgBr-loaded iron oxide/alumina nanocomposite as a promising dual-mode antibacterial and magnetically recoverable photocatalyst material.

High Speed Shearing: A novel approach for high-quality ZnO nanoparticle synthesis and photocatalytic activity control

Zinc oxide (ZnO) nanoparticles show the great promise in photocatalysis due to their exceptional characteristics. However, achieving precise control over ZnO nanoparticle size, morphology, and agglomeration remains a challenge. We applied the high-speed shearing (HSS) method for synthesizing ZnO with enhanced properties. HSS employs a high-speed rotor to generate intense shear forces, enabling efficient particle size reduction, improved homogeneity, and enlarged surface area. HSS method could provide crushing effect and powerful mixing effect to synthesize smaller ZnO nanoparticles with less agglomeration. ZnO nanoparticles are optimized from 9.69 nm to 7.09 nm for single particle and from 955 nm to 26.5 nm for secondary particle size. Ultraviolet diffuse reflectance spectroscopy has been used to further analyze the in-situ formation reaction. Besides, we investigate the photocatalytic efficiency of ZnO towards methylene blue. ZnO nanoparticles made using HSS have more active sites, improving the photocatalytic degradation from 38.6% to 70.8%.