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Search results for: UV-Vis spectroscopy
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Electrooxidation of dissolved dsDNA backed by in situ UV-Vis spectroscopy
PublicationPrzeprowadzono badania elektrochemicznego utleniania dsDNA stosując metody cyklowoltametryczne na elektrodzie weglowej, platynowej, platynowej w formie siatki oraz z siatki platynowej osadzonej na węglu. Otrzymane wyniki analizy spektroelektrochemicznej wykazały, że wraz ze wzrostem potencjału i piku prądowego absorpcja roztworu dsDNA wzrasta w sposób zależny od typu elektrody. Jednak położenie maksimum absorpcji nie zmieniało...
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A facile method for Tauc exponent and corresponding electronic transitions determination in semiconductors directly from UV–Vis spectroscopy data
PublicationIn this work, a facile method allowing for estimation of the exponent in the Tauc equation directly from the UV–vis spectra is presented. It is based on the Taylor expansion of the logarithmic version of the Tauc equation. The Tauc exponent is calculated from the tangent slope of the absorption data. Knowledge of this coefficient provides information about the optical transition types and is used as an input for the calculations...
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UV/VIS Spectroscopy of titanium dioxide coated nickel foams
Open Research DataThe data includes UV-Vis spectra of titanium dioxide coated nickel foams heated at 400, 500 and 600 C in Ar. Jasco V-650 Spectrophotometer was used and Spectra Measurement software.
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Discrimination of Apple Liqueurs (Nalewka) Using a Voltammetric Electronic Tongue, UV-Vis and Raman Spectroscopy
PublicationThe capability of a phthalocyanine-based voltammetric electronic tongue to analyze strong alcoholic beverages has been evaluated and compared with the performance of spectroscopic techniques coupled to chemometrics. Nalewka Polish liqueurs prepared from five apple varieties have been used as a model of strong liqueurs. Principal Component Analysis has demonstrated that the best discrimination between liqueurs prepared from different...
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Hydrophilicity of TiO2 exposed to UV and VIS radiation
PublicationPo raz pierwszy cienka warstwa TiO2 znajdująca się na powierzchni Pilkington Glass AktivTM została poddana modyfikacji za pomocą amoniaku, tiomocznika i mocznika w celu przesunięcia widma absorpcji w kierunku światła widzialnego. Kąty zwilżania dla wody płytek szklanych Pilkington zostały zmierzone dla próbki niezmodyfikowanej i zmodyfikowanej, która odznaczała się zauważalnym przesunięciem spektrum absorpcyjnego w kierunku VIS.
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UV/VIS light-enhanced photocatalysis for water treatment and protection
PublicationPraca zawiera wyniki badań nad zaawansowanymi metodami fotokatalitycznymi w aspekcie degradacji zanieczyszczeń w fazie ciekłej. Fenol i chlorowane pestycydy zostały zastosowane jako związki modelowe. Równocześnie prowadzono badania dotyczące ścieków pestycydowych. Rozważane układy: UV/TiO2 w zawiesinie lub osadzony na szklanych mikrosferach oraz UV/H2O2/powietrze. Poprzez modyfikację tlenku tytanu(IV) pierwiastkami niemetalicznymi...
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Mono- and bimetallic nanoparticles decorated KTaO 3 photocatalysts with improved Vis and UV–Vis light activity
PublicationNew mono- and bimetallic nanoparticle-decorated perovskite-type KTaO3 photocatalysts were successfully synthesized by hydrothermal reaction followed by photodeposition of MNPs/BNPs. The effect of noble metal type, amount of metal precursor as well as photoreduction method on the physicochemical and photocatalytic properties of MNPs- and BNPs-KTaO3 have been investigated. Photocatalytic activity under Vis light irradiation was estimated...
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TiO2 photoactivity in vis and UV light: The influence of calcination temperature and surface properties
PublicationPrzygotowano serię fotokatalizatorów w postaci tlenku tytanu (IV) kalcynowanych w różnych temperaturach od 350 do 750˚C. Charakterystyka fotokatalizatorów za pomocą metod XRD, UV-Vis/DRS, FTIR, XPS, BET oraz BJH wykazała, że próbka TiO2 aktywna w świetle widzialnym posiadała strukturę anatazu, powierzchnię właściwą ok. 200 m2/g, absorbowała światło o długości fali λ>400 nm oraz zawierała 10,1 % at. węgla (wiązanie C-C). Aktywność...
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Validation of Interpolation Algorithms for Multiscale UV-VIS Imaging Using UAV Spectrometer
PublicationIn this study, we present a comparison of popular methods for the interpolation of irregular spatial data in order to determine the applicability of each algorithm for hyperspectral reflectance estimation. The algorithms were benchmarked against a very high-resolution orthoimage from an RGB camera and medium-resolution satellite imagery from Sentinel-2A. We tested five interpolation algorithms: Triangulated Irregular Network (TIN),...
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Chemometric analysis of UV-Vis spektra of associated forms of Amphotericin B and its derivatives
PublicationPrzedmiotem badań był proces agregacji nowych pochodnych antybiotyku polienowego Amfoterycyny B. Do śledzenia procesu agregacji wykorzystano spektroskopię absorpcyjną w zakresie widzialnym i bliskiego nadfioletu. Zastosowanie zaawansowanych technik chemometrycznych pozwoliło na dogłębną analizę agregacji tych pochodnych, co pozwoliło na wyciągniecie następujacych wniosków: i) w przypadku wszystkich pochodnych przy stężeniach poniżej...
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Evaluation of TiO2/UV; O3/UV, and PDS/Vis for improving chlorfenvinphos removal from real municipal treated wastewater effluent
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Otrzymywanie nowych fotokatalizatorów o podwyższonej aktywności w świetle UV oraz VIS
PublicationGłównym celem naukowym pracy było opracowanie nowych metod otrzymywania fotokatalizatorów oraz lepszy zrozumienie mechanizmu ich działania poprzez korelację właściwości powierzchniowych z ich aktywnością fotokatalityczną. Prace badawcze obejmowały preparatykę TiO2 domieszkowanego borem, wolframem i modyfikowanego klastrami metali. Dla otrzymanych nanokompozytów B/TiO2, W/TiO2, Ag/TiO2, Au/TiO2, oraz Pt-TiO2, zbadano aktywność fotokatalityczną...
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Agregacja amfoterycyny B i wybranych pochodnych - chemometryczna analiza widm UV-Vis
PublicationPrezentowane badania miały na celu poznanie procesu agregacji nowej generacji pochodnych polienowego antybiotyku przeciwgrzybowego - amfoterycyny B. Przebieg procesu agregacji w roztworach wodnych o różnym składzie monitorowano przy pomocy absorpcyjnej spektroskopii UV-Vis. Otrzymane zestawy widm analizowano z zastosowaniem zaawansowanych technik chemometrycznych (PCA, NSD), co pozwoliło na określenie liczby, typu i ilości form...
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The Photocatalytic Performance of Benzene- Modified TiO2 Photocatalysts under UV-vis Light Irradiation
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NOWE PODEJSCIE CHEMOMETRYCZNE DO ANALIZY ZESTAWÓW WIDM UV/VIS MIESZANIN DWUSKŁADNIKOWYCH
PublicationW wielu ważnych zagadnieniach z zakresu chemii, biochemii i biofizyki napotykamy problem analizy zestawów widm uzyskanych dla mieszanin dwuskładnikowych. Jeżeli widma obu składników mieszaniny są znane problem sprowadza się do klasycznej kalibracji. W większości zagadnień praktycznych widmo co najmniej jednego ze składników jest nieznane. Prezentowana praca przedstawia propozycję rozwiązania problemu z wykorzystaniem analizy chemometrycznej...
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Antibacterial activity of core-shell CuxO@TiO2 photocatalyst under UV, vis and dark
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photocatalytic activity of silver doped tio2 in vis and uv light, prepared by microemulsion method
PublicationDitlenek tytanu otrzymany w wyniku hydrolizy izopropanolanu tytanu oraz komercyjny katalizator TiO-6 (Catalysis Society of Japan, rutyl, wielkość cząstek 15 nm) zmodyfikowano srebrem metodą mikroemulsyjną. Aktywność fotokatalityczna otrzymanych nanokompozytów Ag-TiO2 została zbadana dla fotodegradacji fenolu pod działaniem promieniowania ultrafioletowego oraz widzialnego. Zaobserwowano, że na efektywność fotorozkładu modelowego...
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Stabilization and Early Degradation of UV-Irradiated Heterophasic Propylene−Ethylene Copolymers Based on ESR, ESR Imaging, UV−Vis, and DSC: Effect of Ethylene Content and UV Wavelength
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Development and validation of an eco-compatible UV–Vis spectrophotometric method for the determination of Cu2+ in aqueous matrices
PublicationCu 2+ are ubiquitous ions in the ecosystem and are responsible of serious environmental pollution. Indeed, the development of sensitive methods for Cu 2+ detection is an urgent demand. In this work, we proposed a new spectrophotometric method for Cu 2+ determination in different water matrices (distilled water, drinking water, wastewater, and river water). The method employs a bio-based organic ligand namely tetrasodium iminodisuccinate...
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Development of New UV–vis Spectroscopic Microwave-Assisted Method for Determination of Glucose in Pharmaceutical Samples
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Evolution of Ag nanostructures created from thin films: UV–vis absorption and its theoretical predictions
PublicationAg-based plasmonic nanostructures were manufactured by thermal annealing of thin metallic films. Structure and morphology were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). SEM images show that the formation of nanostructures is influenced by the initial layer thickness as well as the...
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Photodegradation of phenol by UV/TiO2 and Vis/N,C-TiO2 processes: Comparative mechanistic and kinetic studies
PublicationPorównano drogę fotodegradacji w dwóch systemach badawczych: UV/TiO2 i Vis/N,C-TiO2. Zbadano efektywność degradacji fenolu, powstające produkty pośrednie oraz generowanie rodników hydoksylowych w przygotowanych układach badawczych. Wyniki badań wykazały porównywalne efektywności degradacji fenolu w zawiesinach: domieszkowany TiO2/Vis i TiO2 P-25/UV. Uzyskane wyniki wskazują również na odmienne drogi degradacji zanieczyszczeń w...
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Lanthanide-organic-frameworks modified ZnIn2S4 for boosting hydrogen generation under UV–Vis and visible light
PublicationNovel Ln-MOF with microrods shape were successfully combined with ZnIn2S4 (ZIS) microsphere and used for photocatalytic hydrogen generation under UV–Vis and visible light. The Ln-MOFs/ZIS system comprises lanthanide-carboxylate coordination networks (Tm and Gd as metal ions, and 1,3,5-benzenetricarboxylic acid (BTC) as the organic linker) deposited on ZnIn2S4 microspheres. Effect of the amount of ((Tm,Gd)-BTC) (1, 5, 10 wt%) on...
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UV-Vis measurements and SEM images of Ag nanostructures
Open Research DataUv-vis and SEM of Ag nanostructures. Structures were obtained by dewetting thin films. Various fabrication conditions i.e. temperature, time of the annealing and thickness of the initial layer were subsequently changed.
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Noble metal modified TiO2 microspheres: Surface properties and photocatalytic activity under UV-vis and visible light
PublicationComposite photocatalysts that consist of TiO2and noble metal nanostructures have been considered tobe the promising and pivotal material for accessible enhancement of the efficiency in the photocatalyticprocess carried out in the aqueous and gas phases. In this work we fabricated porous TiO2microspheresthrough a hydrothermal process followed by photochemical reduction of noble metal nanoparticles atthe TiO2surface. The morphology...
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UV-Vis-Induced Degradation of Phenol over Magnetic Photocatalysts Modified with Pt, Pd, Cu and Au Nanoparticles
PublicationThe combination of TiO2 photocatalyst and magnetic oxide nanoparticles enhances the separation and recoverable properties of nanosized TiO2 photocatalyst. Metal-modified (Me = Pd, Au, Pt, Cu) TiO2/SiO2@Fe3O4 nanocomposites were prepared by an ultrasonic-assisted sol-gel method. All prepared samples were characterized by X-ray powder diffraction (XRD) analysis, Brunauer-Emmett-Teller (BET) method, X-ray photoelectron spectroscopy...
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The effect of PEDOT morphology on hexavalent chromium reduction over 2D TiO2/PEDOT photocatalyst under UV–vis light
PublicationThe present study represents an approach to apply organic-inorganic hybrid materials for photocatalytic removal of heavy metals from the aqueous environment. The photocatalytic activity of the semiconductor modified with the conjugated polymer may depends on the conjugated polymer type, its amount and morphology. Therefore, in the present study the effect of poly (3, 4-ethylenedioxythiophene) (PEDOT) morphology on adsorption and photoreduction...
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TiO2 /SrTiO3 and SrTiO3 microspheres decorated with Rh, Ru or Pt nanoparticles: Highly UV–vis responsible photoactivity and mechanism
PublicationA series of TiO2/SrTiO3 and SrTiO3 microspheres decorated by Rh, Ru or Pt NPs were prepared by facile hydrothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) with energy-dispersive Xray (EDX) spectroscopy, scanning electron microscopy (SEM), photoluminescence spectrometry (PL), Fourier transform infrared (FT-IR) and...
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New LED photoreactor with modulated UV–vis light source for efficient degradation of toluene over WO3/TiO2 photocatalyst
PublicationThe efficiencies of prepared WO3/TiO2 photocatalysts with varying amounts of WO3 were evaluated for gas-phase photocatalytic degradation of toluene. The obtained results revealed that the best photocatalytic properties were characteristic for samples calcined at 500ºC, which can be associated with high crystalline phase content (> 97%) and favourable BET surface area. The photocatalytic degradation tests were performed in two photoreactors...
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Determination of Zinc, Copper, and Mercury in Water Samples by Using Novel Micro Cloud Point Extraction and UV-Vis Spectrophotometry
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Thermal and spectroscopic profiles variation of cold-pressed raspberry seed oil studied by DSC, UV/VIS, and FTIR techniques
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Rare earth ions doped K 2 Ta 2 O 6 photocatalysts with enhanced UV–vis light activity
PublicationNew rare earth-doped K2Ta2O6 photocatalysts were successfully synthesized by hydrothermal method. The effect of dopant type (Y,Yb,Ho,Pr,Er) and amount of rare earth precursor (2,4,8 and 10 mol%) on the physicochemical and photocatalytic properties of RE-K2Ta2O6 have been investigated. All as-prepared materials were characterized by UV–vis diffuse reflectance spectroscopy, Brunauer-Emmett-Teller specific surface area measurement,...
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Mono- and bimetallic (Pt/Cu) titanium(IV) oxide core–shell photocatalysts with UV/Vis light activity and magnetic separability
PublicationTitanium(IV) oxide is one of the most widely investigated photocatalysts. However, separation of nano-sized particulate titania might result in profitless technologies for commercial applications. Additionally, bare titania is almost inactive under the Vis range of solar spectrum due to its wide bandgap. Therefore, the present study aims to prepare novel coreinterlayer- shell TiO2 magnetic photocatalysts modified with metal nanoparticles...
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Copper(II) complexes with substituted imidazole and chlorido ligands: X-ray, UV-Vis, magnetic and EPR studies and chemotherapeutic potential
PublicationCrystal structures, UV-Vis and EPR spectra and magnetic properties of four copper(II) complexes with chloride anions and 4-methylimidazole, 2-ethylimidazole, 2-isopropylimidazole or 2-ethyl-4-methylimidazole are described. In the solid state three of the complexes are mononuclear and one complex with 2-ethylimidazole is binuclear with bridging chlorido ions. UV-Vis spectra of the methanolic solutions of the complexes show LMCT...
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UV-Vis-DR-TiO2 heated at 400-600oC in Ar or H2
Open Research DataThese data contain UV-Vis/DR spectra of TiO2 heated at 400-600oC in Ar or H2. Transformation of spectra to Kubelka-Munk function was performed together with determination of band gap.
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Solvation of cobalt(II) ion in N,N-dimethylformamide-methanol mixed solvent: calorimetry and VIS spectroscopy studies
PublicationZmierzono entalpie rozpuszczania trifluorometanosulfonianów Co(II) i Na(I) w mieszaninie N,N-dimetyloformamid(DMF)-metanol(MeOH) w całym zakresie jej składu. Z danych tych wyznaczono entalpie przeniesienia jonu Co(II) i jonu trifluorometanosulfonowego. Wyniki zanalizowano za pomocą teorii solwatacji preferencyjnej. Zmierzono również widma w zakresie widzialnym roztworów jonu Co(II) w mieszaninie DMF-MeOH i zanalizowano je, stosując...
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Copper(II) complexes with substituted imidazole and chlorido ligands: X-ray, UV–Vis, magnetic and EPR studies and chemotherapeutic potential
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Preparation and photocatalytic activity of boron-modified TiO2 under UV and visible light
PublicationOtrzymano TiO2 domieszkowany borem i wyznaczono jego aktywność fotokatalityczną w zakresie światła UV i Vis. Katalizatory otrzymano metodą zol-żel lub poprzez ucieranie dwutlenku tytanu z prekursorami B. Jako źródło boru zastosowano kwas borowy lub ester trietylowy kwasu borowego. Fotoaktywność próbek badano w reakcji degradacji fenolu (Co = 0,21 mmol/dm3 ) w zakresie światła Vis lub UV. Obecność węgla i boru we wszystkich przygotowanych...
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Metodyka oznaczania sumarycznej zawartości inhibitorów fermentacji ciemnej oraz monocukrów w brzeczkach fermentacyjnych techniką HPLC-RID-UV-VIS/DAD
PublicationW pracy przedstawiono wyniki badań oraz opracowaną w ich rezultacie metodykę ilościowego oznaczania sumarycznej zawartości inhibitorów fermentacji ciemnej oraz monocukrów w brzeczkach fermentacyjnych z wykorzystaniem techniki chromatografii cieczowej (RP-HPLC-RID-UV-VIS/DAD). Najbardziej przydatną do zbadania sumarycznej zawartości inhibitorów w próbkach rzeczywistych okazało się zastosowanie warunków chromatografii wykluczania...
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UV-VIS spectra of adsorption of methyl orange (MO) and methylene blue (MB) by porous carbon material
Open Research DataThis dataset contains UV-VIS spectra of adsorption of dyes: methyl orange (MO) and methylene blue (MB) by porous carbon material.
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Ewa Wagner-Wysiecka dr hab. inż.
PeopleEwa Wagner-Wysiecka is a graduate of the Faculty of Chemistry at Gdańsk University of Technology (specializing in Chemical Technology, with a focus on Inorganic Technology and a sub-specialty in Technical and Industrial Analytics). She completed her master's thesis, entitled "Identification of Contaminants in Pharmacopoeial Sulfaquinoxaline," under the supervision of Professor Jan F. Biernat. After completing her master's degree...
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Stability of borophene dispersion in water
Open Research DataThis dataset contains the results of the studies of stability of borophene dispersion in water (1 µg/µL) based on the measurements of absorbance of the solution using UV-VIS spectroscopy.
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Research 1: Heterojunction of (P, S) co-doped g-C3N4 and 2D TiO2 for improved carbamazepine and acetaminophen photocatalytic degradation
Open Research DataThe first research article consisted on the synthesis of phosphorus and sulfur co-doped graphitic carbon nitride incorporated in 2D TiO2 structure for solar-driven degradation of emerging pollutants from the group of pharmaceuticals not susceptible to biodegradation. The hybrid photocatalysts with different loadings of (P, S)-doped g-C3N4 were characterized...
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Optical measurements of LTO:Cu sol-gel derived thin films
Open Research DataLithium titanate doped by copper thin films were manufactured by chemical, sol-gel method. Flms were deposited on a Corning glass substrated by spin coater. To calculated optical band gap and other optcal parameters, UV-VIS spectroscopy measurements were performed. For measurements selected samples with various content of Cu.
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Ultra-thin film of aluminum oxide influence on the plasmon resonance in gold nanostructures
Open Research DataUltra-thin film of aluminum oxide influence on the plasmon resonance in gold nanostructures was measured by UV-VIS spectroscopy. Ultra thin film of Al2O3 was deposited on a gold nanostructures. Thickness of film was 2nm - 8nm. Shift of plasmon resonance was observed, as a result of various dielectric constant of layer.
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Preparation and photocatalytic properties of BaZrO 3 and SrZrO 3 modified with Cu 2 O/Bi 2 O 3 quantum dots
PublicationIn this study, we report a novel method of BaZrO3 and SrZrO3 surface modification by two different types of quantum dots (QDs, Cu2O and Bi2O3), which improved the photocatalytic performance of the obtained materials under UV-Vis light irradiation. Pristine BaZrO3 and SrZrO3 were prepared by the hydrothermal method. The deposition of Cu2O- and Bi2O3-QDs was carried out by chemical reduction. The morphology of the nanoparticles was...
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Preparation and Characterization of Defective TiO2. The Effect of the Reaction Environment on Titanium Vacancies Formation
PublicationAmong various methods of improving visible light activity of titanium(IV) oxide, the formation of defects and vacancies (both oxygen and titanium) in the crystal structure of TiO2 is an easy and relatively cheap alternative to improve the photocatalytic activity. In the presented work, visible light active defective TiO2 was obtained by the hydrothermal reaction in the presence of three different oxidizing agents: HIO3, H2O2, and...
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Photocatalytic and Antimicrobial Properties of Ag2O/TiO2 Heterojunction
PublicationAg2O/TiO2 heterojunctions were prepared by a simple method, i.e., the grinding of argentous oxide with six different titania photocatalysts. The physicochemical properties of the obtained photocatalysts were characterized by diffuse-reflectance spectroscopy (DRS), X-ray powder diffraction (XRD) and scanning transmission electron microscopy (STEM) with an energy dispersive X-ray spectroscopy (EDS). The photocatalytic activity was...
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Novel nitrogen precursors for electrochemically driven doping of titania nanotubes exhibiting enhanced photoactivity
PublicationNitrogen doped titania nanotubes were successfully sensitized by electrochemical method, i.e. as-anodized titania was immersed in different amine (diethyleneamine-DETA, triethyleneamine-TEA, ethylenediamine-EDA) and urea (U) solution and a constant potential was applied. The highly ordered morphology of fabricated N-TiO2 was investigated by using scanning electron microscopy. Spectroscopic techniques, i.e. UV-Vis spectroscopy,...
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Defective TiO2 Core-Shell Magnetic Photocatalyst Modified with Plasmonic Nanoparticles for Visible Light-Induced Photocatalytic Activity
PublicationIn the presented work, for the first time, the metal-modified defective titanium(IV) oxide nanoparticles with well-defined titanium vacancies, was successfully obtained. Introducing platinum and copper nanoparticles (NPs) as surface modifiers of defective d-TiO2 significantly increased the photocatalytic activity in both UV-Vis and Vis light ranges. Moreover, metal NPs deposition on the magnetic core allowed for the effective separation...