0000000000124999

AUTHOR

María González-béjar

0000-0001-5434-4210

showing 45 related works from this author

Photoactive Hybrid Materials based on Conjugated Porous Polymers and Inorganic Nanoparticles

2021

This review explores the current state‐of‐the‐art for functional photoactive hybrids containing inorganic nanoparticles (magnetic and metal) and conjugated organic porous polymers (CPPs). Albeit new in the field, with the first hybrid material of this kind reported in 2012, those materials have gained increasing interest in applications such as sensing, heterogeneous catalysis, photocatalysis, and lithium‐ion batteries (LIBs). This review describes the two main synthetic strategies for those materials, namely, 1) using the chemical and morphological features (e.g., porosity and complexation sites) of CPPs to in situ form nanoparticles and 2) fabricating the nanoparticle for templating CPPs.…

chemistry.chemical_classificationconjugated porous polymersmagnetic nanoparticlesMaterials scienceQC350-467General MedicinePolymerphotoactive hybrid materialsOptics. LightConjugated systemTA1501-1820Chemical engineeringchemistryMagnetic nanoparticlesApplied optics. Photonicsmetal nanoparticlesPorosityMetal nanoparticlesHybrid materialInorganic nanoparticlesAdvanced Photonics Research
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In Situ Colorimetric Quantification of Silver Cations in the Presence of Silver Nanoparticles

2013

Silver ions (Ag(+)) can be quantified in situ in the presence of AgNPs by using a colorimetric sensing probe (3,3',5,5'-tetramethylbenzidine). Interestingly, it also enables detection of the Ag(+) adsorbed on the AgNP surface. This is relevant to design new methods to make AgNPs while ensuring the total reduction of Ag(+).

In situAdsorptionChemistryInorganic chemistrySilver nanoparticleAnalytical ChemistryIonAnalytical Chemistry
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CO2 switchable nanoparticles: reversible water/organic-phase exchange of gold nanoparticles by gas bubbling

2013

Gold nanoparticles capped with oleylamine can be effectively transferred from an organic solvent to water in the presence of an acetamidine surfactant by CO2 bubbling and then effectively reverted back to the organic phase by N2 bubbling.

chemistry.chemical_compoundPulmonary surfactantChemistryOleylamineColloidal goldGeneral Chemical EngineeringOrganic solventPhase (matter)Inorganic chemistryfood and beveragesNanoparticleGeneral ChemistryRSC Advances
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Upconversion luminescent nanoparticles in physical sensing and in monitoring physical processes in biological samples.

2015

The most frequently used strategy for sensing is based on the emission variation of a photoactive system and it can be classified as chemical or physical depending on its response to either a chemical or a physical stimulus. There are a large number of luminescent nanomaterials that respond to chemical species, but comparatively, with the exception of temperature sensing, to date there are few examples showing the capacity of photoactive nanosystems responsive to physical stimuli, such as magnetic and electric fields, high radiation energy, tension/pressure, viscosity, etc, and very few of them comprise upconversion nanoparticles (UCNPs). These nanomaterials consist of an inorganic matrix d…

Materials sciencebusiness.industryDopingNanoparticleNanotechnologyAtomic and Molecular Physics and OpticsPhoton upconversionNanomaterialsIonChemical speciesOptoelectronicsGeneral Materials SciencebusinessLuminescenceInstrumentationSpectroscopyExcitationMethods and applications in fluorescence
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Enhanced catalytic electrochemical reduction of dissolved oxygen with ultracleancucurbituril[7]-capped gold nanoparticles

2014

Gold nanoparticles capped with cucurbituril[7] have been prepared in the absence of metallic cations and organic ligands. Remarkably, these nanohybrids encapsulate dissolved oxygen and are highly active in electrochemical reduction. The effect of the presence of sodium and ammonium salts on this catalysed process is also analysed.

SodiumInorganic chemistrychemistry.chemical_elementElectrochemistryCatalysisMetalchemistry.chemical_compoundchemistryColloidal goldCucurbiturilvisual_artvisual_art.visual_art_mediumGeneral Materials ScienceAmmonium
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Lengthening the Lifetime of Common Emissive Probes to Microseconds by a Jigsaw‐Like Construction of NIR‐Responsive Nanohybrids

2020

MicrosecondUpconversion nanoparticlesMaterials scienceNanotechnologyAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsJigsawAdvanced Optical Materials
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Gold nanoparticle catalysis of the cis-trans isomerization of azobenzene

2013

Ablated, “pseudo-naked” gold nanoparticles (AuNPs) catalyze the cis–trans isomerization of substituted azobenzenes. para-Substitution was found to affect the rate of isomerization, suggesting the participation of AuNP-mediated electron transfer in the isomerization mechanism. Fil: Hallet Tapley, Geniece. University of Ottawa; Canadá Fil: D'Alfonso, Claudio. University of Ottawa; Canadá. Universita Di Roma; Italia Fil: Pacioni, Natalia Lorena. University of Ottawa; Canadá Fil: McTiernan, Cristopher D.. University of Ottawa; Canadá Fil: Gonzalez Bejar, Maria. University of Ottawa; Canadá. Universidad de Valencia; España Fil: Lanzalunga, Osvaldo. Universita Di Roma; Italia Fil: Alarcon, Emilio…

NanoparticleNANOCATALYSIS010402 general chemistryPhotochemistry01 natural sciencesCatalysisCatalysisElectron transferchemistry.chemical_compoundMaterials ChemistryGOLDISOMERIZATION010405 organic chemistryChemistryOtras Ciencias QuímicasCiencias QuímicasMetals and AlloysGeneral ChemistryCis trans isomerization0104 chemical sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsAZOBENZENESAzobenzeneColloidal goldCeramics and CompositesIsomerizationCIENCIAS NATURALES Y EXACTAS
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Adenosine monophosphate-capped gold(i) nanoclusters: synthesis and lanthanide ion-induced enhancement of their luminescence

2016

Reduction of Au3+ in the presence of just adenosine 5′-monophosphate (AMP) and a zwitterionic organic chemical buffering agent, specifically 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES), combined with light exposure, gives rise to luminescent, water-soluble Au+ nanoclusters (Au+ NCs). The photoluminescence of these NCs is considerably enhanced by adding Y3+ or the chemically similar Yb3+ lanthanide that leads to Au+/Y3+ and Au+/Yb3+ NCs, respectively. These NCs are characterised by absorption (steady-state), photoluminescence (steady-state and time-resolved), and X-ray photoelectron spectroscopy.

Adenosine monophosphateHEPESLanthanidePhotoluminescenceGeneral Chemical Engineering02 engineering and technologyGeneral Chemistry010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistry01 natural sciences0104 chemical sciencesNanoclusterschemistry.chemical_compoundchemistryX-ray photoelectron spectroscopyAbsorption (chemistry)0210 nano-technologyLuminescenceRSC Advances
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Application of the Generalized Molar-Ratio Method to the Determination of the Stoichiometry and Apparent Binding Constant of Nanoparticle-Organic Cap…

2015

A generalization of the molar-ratio method is applied to the determination of the stoichiometry and apparent binding constant of metal nanoparticle-organic capping complexes (MmLx) using voltammetric data for the oxygen reduction reaction (ORR) in air-saturated aqueous phosphate buffer solutions. The method is applied to the formation of binary nanohybrids consisting of gold nanoparticles (AuNPs) capped with a rigid spacer, cucurbit[7]uril (CB), termed AuNP@CB, as well as to the formation of their ternary complexes (MmLxBz) with methylene blue (MB), termed AuNP@CB@MB. The obtained stoichiometries correspond to binding of four Au surface atoms for each CB unit.

Aqueous solutionChemistryInorganic chemistryNanoparticleBinding constantAnalytical ChemistryMetalCucurbiturilColloidal goldvisual_artElectrochemistryvisual_art.visual_art_mediumTernary operationStoichiometryElectroanalysis
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Thin Amphiphilic Polymer-Capped Upconversion Nanoparticles: Enhanced Emission and Thermoresponsive Properties

2014

Upconversion nanoparticles (ß-NaYF4:Er3+, Yb3+, UCNPs) were capped with a thin polymer shell by replacing the oleate ligand of hydrophobic UCNPs by multidentate thiolate-grafting of P(MEO2MA-co-SEMA) copolymers. The presence of the 2-(2-methoxyethoxy)ethyl side chains of MEO2MA extending out of the nanohybrid made them water-dispersible. The UCNP@P(MEO2MA-co-SEMA) nanohybrids exhibited an enhanced emission by up to a factor of 10, as compared with that of their hydrophobic precursor in dichloromethane and even in water (a factor of 2). Moreover, their thermoresponsiveness was modulated by the pH; this is consistent with the presence of some thiol groups at the nanohybrid periphery. Remarkab…

chemistry.chemical_classificationDenticityMaterials scienceLigandGeneral Chemical EngineeringGeneral ChemistryPolymerAtmospheric temperature rangechemistry.chemical_compoundchemistryChemical engineeringAmphiphileMaterials ChemistryCopolymerSide chainOrganic chemistryDichloromethaneChemistry of Materials
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Breaking the Nd3+-sensitized upconversion nanoparticles myth about the need of onion-layered structures

2018

Up to now, most strategies to build efficient 800 nm-light responsive upconversion nanoparticles (UCNPs) have included onion-layered structures, in which Nd3+ is confined within the inorganic crystal structure of at least one layer. We report here an easy room-temperature modular preparation of core-shell UCNPs consisting of NaYF4:Yb,Er(Tm)/NaYF4 (UCCS) with Nd3+ anchored at the organic capping by using cucurbituril[7] (CB[7]) as an adhesive. Strikingly, excitation at 800 nm effectively triggers the upconversion emission of UCCS@CB[7]@Nd nanohybrids.

Materials scienceNanotechnology02 engineering and technologyCrystal structure010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesPhoton upconversion0104 chemical sciencesUpconversion nanoparticlesCucurbiturilGeneral Materials Science0210 nano-technologyLayer (electronics)Nanoscale
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Pyrene-benzoylthiophene Bichromophores as Selective Triplet Photosensitizers.

2006

Combination of the pyrene and benzoylthiophene units constitutes an interesting approach to design bichromophoric photosensitizers with increased intersystem crossing quantum yield and enhanced selectivity. The potential of this strategy has been illustrated in the present work by using a model photoisomerization reaction.

PhotoisomerizationChemistryMetals and AlloysQuantum yieldGeneral ChemistryGeneral MedicinePhotochemistryThiophene derivativesCatalysisSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialschemistry.chemical_compoundIntersystem crossingMaterials ChemistryCeramics and CompositesPyreneEnhanced selectivityChemInform
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Upconversion Nanoparticles for Bioimaging and Regenerative Medicine.

2016

Nanomaterials are proving useful for regenerative medicine in combination with stem cell therapy. Nanoparticles can be administrated and targeted to desired tissues or organs and subsequently, be used in non-invasive real-time visualization and tracking of cells by means of different imaging techniques, they can act as therapeutic agent nanocarriers, and can also serve as scaffolds to guide the growth of new tissue. Nanoparticles can be of different chemical nature, such as gold, iron oxide, cadmium selenide, and carbon, and have the potential to be used in regenerative medicine. However, there are still many issues to be solved, such as toxicity, stability, and resident time. Upconversion …

Materials scienceHistologyMini ReviewBiomedical EngineeringNanoparticleNanotechnologyBioengineering02 engineering and technology010402 general chemistry01 natural sciencesRegenerative medicineNanomaterialschemistry.chemical_compoundUpconversion nanoparticlestransparencyCadmium selenideLow toxicityNIR excitationnon-toxic nanoparticlescell behavior regulationfungifood and beveragesBioengineering and Biotechnology021001 nanoscience & nanotechnologymulti-wavelength/multimodal bioimagingPhoton upconversion0104 chemical scienceschemistryupconverted (UV–VIS–NIR) emissionNanocarriers0210 nano-technologyBiotechnologyFrontiers in bioengineering and biotechnology
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Nanohybrid for Photodynamic Therapy and Fluorescence Imaging Tracking without Therapy

2018

Theranostic upconversion nanoparticles (UCNPs) are ideal candidates for personalized medicine. We present a smart, easy-to-prepare nanohybrid (NH) suitable for NIR-theragnosis and imaging tracking without triggering therapy simultaneously. The photophysical features of each component have been carefully selected in order to maximize the capabilities for theragnosis, in particular, the upconversion emission and the photosensitizer absorption. In addition, NH presents a fluorescent marker with one-photon absorption in the green and two-photon absorption cross-section at NIR wavelengths where the UCNP does not absorb, thus enabling innocuous tracking. Thus, the NH consists of NaYF4:Yb, Er, Tm …

Fluorescence-lifetime imaging microscopyMaterials scienceGeneral Chemical Engineeringmedicine.medical_treatmentPhotodynamic therapy02 engineering and technologyGeneral Chemistry010402 general chemistry021001 nanoscience & nanotechnologyTracking (particle physics)Photochemistry01 natural sciencesFluorescencePorphyrinPhoton upconversion0104 chemical scienceschemistry.chemical_compoundchemistryMaterials ChemistrymedicinePhotosensitizer0210 nano-technologyAbsorption (electromagnetic radiation)Chemistry of Materials
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NIR excitation of upconversion nanohybrids containing a surface grafted Bodipy induces oxygen-mediated cancer cell death

2020

We report the preparation of water-dispersible, ca. 30 nm-sized nanohybrids containing NaYF4:Er3+, Yb3+ up-conversion nanoparticles (UCNPs), capped with a polyethylene glycol (PEG) derivative and highly loaded with a singlet oxygen photosensitizer, specifically a diiodo-substituted Bodipy (IBDP). The photosensitizer, bearing a carboxylic group, was anchored to the UCNP surface and, at the same time, embedded in the PEG capping; the combined action of the UCNP surface and PEG facilitated the loading for an effective energy transfer and, additionally, avoided photosensitizer leaching from the nanohybrid (UCNP-IBDP@PEG). The effectiveness of the nanohybrids in generating singlet oxygen after n…

Materials scienceSinglet oxygentechnology industry and agricultureBiomedical Engineeringchemistry.chemical_elementNanoparticleGeneral ChemistryGeneral MedicinePolyethylene glycolPhotochemistryOxygenPhoton upconversionchemistry.chemical_compoundchemistryPEG ratioGeneral Materials SciencePhotosensitizerBODIPYJ. Mater. Chem. B
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Mechanism of triplet photosensitized Diels-Alder Reaction between indoles and cyclohexadienes: theoretical support for an adiabatic pathway.

2006

Diels-Alder reactions between indoles (InHs) and 1,3-cyclohexadienes (CHDs) were achieved by using aromatic ketones as photosensitizers. For instance, irradiation of deaerated dichloromethane solutions containing benzoylthiophene (BT, 1 mM), indole (20 mM), and phellandrene (40 mM), in the presence of an acylating agent, led to the N-acetylated Diels-Alder cycloadduct in 46% yield (endo:exo ratio of 1.8:1). Energy transfer from the BT triplet to the CHD gave rise to diene dimers as byproducts. Several combinations of CHDs, InHs, and aromatic ketones were tested; the Diels-Alder reaction was found to be a general process, except when the indole nucleus was substituted at position 2 or 7 and …

Indole testchemistry.chemical_classificationchemistry.chemical_compoundReaction mechanismKetoneDienechemistryOrganic ChemistryCyclohexadienesAromatizationTriplet statePhotochemistryDiels–Alder reactionThe Journal of organic chemistry
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Pyrene-benzoylthiophene exciplexes as selective catalysts for the [2+2] cycloaddition between cyclohexadiene and styrenes.

2007

Efficient intramolecular fluorescence quenching in pyrene−benzoylthiophene systems leads to formation of exciplexes. These species interact with 1,3-cyclohexadiene (or styrenes), leading to reactive excited triplexes. The overall process affords [2+2] cross-cycloadducts with an average yield of 57%.

chemistry.chemical_compoundchemistryExcited stateYield (chemistry)Intramolecular forceOrganic ChemistryPyrenePhysical and Theoretical ChemistryPhotochemistryBiochemistryCycloadditionCatalysisOrganic letters
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Initial Biological Assessment of Upconversion Nanohybrids

2021

Nanoparticles for medical use should be non-cytotoxic and free of bacterial contamination. Upconversion nanoparticles (UCNPs) coated with cucurbit[7]uril (CB[7]) made by combining UCNPs free of oleic acid, here termed bare UCNPs (UCn), and CB[7], i.e., UC@CB[7] nanohybrids, could be used as photoactive inorganic-organic hybrid scaffolds for biological applications. UCNPs, in general, are not considered to be highly toxic materials, but the release of fluorides and lanthanides upon their dissolution may cause cytotoxicity. To identify potential adverse effects of the nanoparticles, dehydrogenase activity of endothelial cells, exposed to various concentrations of the UCNPs, was determined. Da…

Programmed cell deathQH301-705.5Medicine (miscellaneous)Nanoparticle02 engineering and technology010402 general chemistry01 natural sciencesArticleGeneral Biochemistry Genetics and Molecular BiologyHeLachemistry.chemical_compoundLysosomeLactate dehydrogenasemedicineBiology (General)Cytotoxicitybiology021001 nanoscience & nanotechnologybiology.organism_classificationPhoton upconversion0104 chemical sciencescucurbiturilupconversion nanoparticlesmedicine.anatomical_structurechemistryApoptosisBiophysicscytotoxicity0210 nano-technologyBiomedicines
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NIR laser scanning microscopy for photophysical characterization of upconversion nanoparticles and nanohybrids

2021

Photophysical characterization of upconversion nanoparticles (UCNPs) and nanohybrids (UCNHs) is more challenging than that of down-conversion nanomaterials. Moreover, it is still difficult to gain knowledge about the homogeneity of the sample and colocalization of emissive chromophores and nanoparticles in nanohybrids. Near infrared laser scanning microscopy (NIR-LSM) is a well-known and useful imaging technique, which enables excitation in the NIR region and has been extensively applied to optical fluorescence imaging of organic fluorophores and nanomaterials, such as quantum dots, which exhibit a short-lived emission. NIR-LSM has recently been used to determine the empirical emission life…

chemistry.chemical_compoundMaterials scienceFluorophorechemistryQuantum dotColocalizationNanoparticleGeneral Materials ScienceNanotechnologyChromophoreNanomaterialsCharacterization (materials science)Scanning microscopyNanoscale
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Polysulfonate Cappings on Upconversion Nanoparticles Prevent Their Disintegration in Water and Provide Superior Stability in a Highly Acidic Medium

2018

The stability of organic cappings on hexagonal NaYF4:Ln3+ upconversion nanoparticles (UCNPs) is crucial for their luminescence efficiency in aqueous solutions. The capping removal quickens as the acidity of the medium increases. We demonstrate here that polysulfonates, namely poly(2-acrylamido-2-methyl-1-propanesulfonate) (PAMPS) and poly(sodium 4-styrene sulfonate) (PSS), remain anchored to the surface of NaYF4:Yb3+,Er3+/Tm3 UCNPs even at a pH as low as 2 due to strong acidity of the sulfonate anchoring groups (pKa of ca. −3). Bare UCNPs progressively disintegrate into their compositional F–, Na+, Y3+, and Ln3+ ions. Their disintegration is particularly worrying in highly diluted dispersio…

LanthanideAqueous solutionChemistryGeneral Chemical EngineeringSodiumNanoparticlechemistry.chemical_elementGeneral ChemistryArticleIonlcsh:ChemistryUpconversion nanoparticleschemistry.chemical_compoundSulfonateChemical engineeringlcsh:QD1-999LuminescenceACS Omega
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Sensitive and selective plasmonic assay for spermine as biomarker in human urine.

2014

A simple, fast, and highly selective and sensitive colorimetric assay to detect nanomolar levels of spermine in human urine (healthy donors, cancer patients) is reported. This assay is based on the absence of a competitive organic capping on the gold nanoparticles together with the high affinity of the amine groups of the analyte for the nanoparticle surface.

AnalyteChromatographyChemistrySpermineMetal NanoparticlesUrineUrinalysisHighly selective3. Good healthAnalytical Chemistrychemistry.chemical_compoundBiomarkerBiochemistryColloidal goldLimit of DetectionHumansAmine gas treatingColorimetrySpermineGoldBiomarkersAnalytical chemistry
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Upconversion nanoparticles with a strong acid-resistant capping

2016

Water-dispersible upconversion nanoparticles (β-NaYF:Yb,Er, UCNP) coated with a thin shell of a biocompatible copolymer comprising 2-hydroxyethylmethacrylate (HEMA) and 2-acrylamido-2-methyl-1-propanesulphonsulphonic acid (AMPS), which we will term COP, have been prepared by multidentate grafting. This capping is remarkably resistant to strong acidic conditions as low as pH 2. The additional functionality of the smart UCNP@COP nanosystem has been proved by its association to a well-known photosensitizer (namely, methylene blue, MB). The green-to-red emission ratio of the UC@COP@MB nanohybrid exhibits excellent linear dependence in the 7 to 2 pH range as a consequence of the release of the d…

DenticityMaterials science02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnologyGraftingBiocompatible material01 natural scienceshumanities0104 chemical sciencesUpconversion nanoparticleschemistry.chemical_compoundchemistryPh rangeCopolymerOrganic chemistryGeneral Materials SciencePhotosensitizer0210 nano-technologyMethylene blueNuclear chemistry
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The Luminescence of CH3NH3PbBr3Perovskite Nanoparticles Crests the Summit and Their Photostability under Wet Conditions is Enhanced

2016

CH3 NH3 PbBr3 perovskite nanoparticles (PAD ) are prepared with a photoluminescence quantum yield of ≈100% in air atmosphere by using the quasi-spherical shaped 2-adamantylammonium bromide (ADBr) as the only capping ligand. The photostability under wet conditions of this kind of nanoparticles is enhanced by using cucurbit[7]uril-adamantylammonium (AD@CB) host-guest complexes as the capping ligand.

PhotoluminescenceMaterials scienceLigandInorganic chemistryNanoparticleQuantum yield02 engineering and technologyGeneral Chemistry010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistry01 natural sciences0104 chemical sciencesBiomaterialschemistry.chemical_compoundchemistryBromideCucurbiturilGeneral Materials Science0210 nano-technologyLuminescenceBiotechnologyPerovskite (structure)Small
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Understanding light-driven H2 evolution through the electronic tuning of aminopyridine cobalt complexes† †Electronic supplementary information (ESI) …

2017

Electronic effects provide a general mechanistic scenario for rationalizing photocatalytic water reduction activity with aminopyridine cobalt complexes.

inorganic chemicalsChemistryfood and beveragesChemical Science
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Linear Coassembly of Upconversion and Perovskite Nanoparticles: Sensitized Upconversion Emission of Perovskites by Lanthanide‐Doped Nanoparticles

2020

Sensitized emission of lead halide perovskite nanoparticles (LHPNPs) can be achieved by near‐infrared (NIR) excitation of nearby lanthanide‐doped upconversion nanoparticles (UCNPs) by using a low‐cost diode laser. Here, the first preparation of linear assemblies of core and core–shell NPs, as well as linear coassemblies of LHPNPs and UCNPs, within an open peapod‐like lead sulfate shell are reported. UCNPs with a NaYF4 matrix doped with ytterbium and thulium or erbium, and with an inert shell of NaYF4 in the case of core‐shell, and all‐inorganic CsPbX3 NPs (X = halide) are chosen for these studies. Interestingly, the lead sulfate shell enhances the luminescence of the core/core– shell UCNPs …

YtterbiumLanthanideMaterials sciencechemistry.chemical_elementNanoparticle02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnologyCondensed Matter Physics01 natural sciencesPhoton upconversion0104 chemical sciencesElectronic Optical and Magnetic MaterialsBiomaterialsErbiumThuliumchemistryChemical engineeringElectrochemistry0210 nano-technologyLuminescencePerovskite (structure)Advanced Functional Materials
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Texture and Phase Recognition Analysis of beta-NaYF4 Nanocrystals

2014

Texture and phase recognition analysis (TPRA) based on electron nanodiffraction technique is used to characterize the geometry of up-conversion nanocrystals (UCNCs) synthesized by the common thermal-decomposition protocol in the presence of a stoichiometric amount of NH4F. Here, we confirmed experimentally that despite the apparently different shapes of samples (hexagons, rods, and cubes), all the nanocrystals are actually beta-phase hexagonal prisms. This is of relevance since many biological features of nanostructures, such as cellular internalization and cytotoxicity, are governed by their geometry. In addition, reproducibility in biological experiments is paramount.

Materials scienceNanostructuregenetic structuresHexagonal crystal systemRodSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsCrystallographyGeneral EnergyNanocrystalPhase (matter)Texture (crystalline)Physical and Theoretical ChemistryStoichiometry
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Cucurbit[n]uril-capped upconversion nanoparticles as highly emissive scaffolds for energy acceptors.

2015

Spontaneous adsorption of cucurbit[n]uril CB[n] (n = 6, 7, and 8) on the surface of naked upconversion nanoparticles (UCNPs), in particular, NaYF4:Er3+(2%),Yb3+(18%) gave rise to UCNP@CB[n] exclusion complexes. These complexes proved to be highly stable as well as highly emissive under near-infrared excitation. By using two tricyclic basic dyes (specifically, methylene blue and pyronin Y) as a proof of concept, we demonstrate that the UCNP@CB[n] (n = 6, 7) nanohybrids can form exclusion complexes with this type of dyes via the CB carbonyl free portal, i.e., UCNP@CB@dye hybrids, thus making it possible to locate a high concentration of the dyes close to the UCNP and, consequently, leading to…

chemistry.chemical_compoundUpconversion nanoparticlesMaterials scienceAdsorptionchemistryOrganic chemistryGeneral Materials SciencePhotochemistryPyronin yMethylene blueNanoscale
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Ketorolac beats ketoprofen: lower photodecarboxylation, photohemolysis and phototoxicity

2013

Ketorolac shows reduced photohemolytic activity and low phototoxicity against human skin fibroblasts when compared to ketoprofen. The low decarboxylation quantum yield together with the efficient non-radiative deactivation of the triplet and singlet excited states of ketorolac are believed to be responsible for this behaviour.

PharmacologyKetoprofenDecarboxylationChemistryOrganic ChemistryPharmaceutical ScienceQuantum yieldHuman skinPharmacologyPhotochemistryBiochemistryKetorolacExcited stateDrug DiscoverymedicineMolecular MedicineSinglet statePhototoxicitymedicine.drugMedChemComm
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Rapid one-pot propargylamine synthesis by plasmon mediated catalysis with gold nanoparticles on ZnO under ambient conditions

2013

Surface plasmon excitation of gold nanoparticles on ZnO in the presence of an aldehyde, an amine and phenylacetylene led to rapid and selective formation of propargylamines with good yields (50-95%) at room temperature. Plasmon mediated catalysis is the best available route for this ternary coupling.

Materials scienceMetal Nanoparticles010402 general chemistryPhotochemistry01 natural sciencesAldehydeCatalysisCatalysischemistry.chemical_compoundMaterials ChemistrySurface plasmon excitationAminesPlasmonchemistry.chemical_classificationAldehydesPropylamines010405 organic chemistryTemperatureMetals and AlloysGeneral Chemistry0104 chemical sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsPargylinechemistryPhenylacetyleneColloidal goldAlkynesCeramics and CompositesAmine gas treatingGoldZinc OxideTernary operationChemical Communications
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Silver Nanoparticles in Heterogeneous Plasmon Mediated Catalysis

2015

Metallic nanoparticles are considered a new class of heterogeneous photocatalysts due to their ability to absorb solar light and convert it into chemical energy. Here, we focus on the use of silver nanoparticles in light driven catalytic processes. This chapter will start with a brief introduction to the currently available nanocomposites that contain silver nanoparticles. Then, the mechanisms behind the photocatalytic activity of those nanocomposites will be discussed.

Chemical energyNanocompositeMaterials scienceSolar lightLight drivenPhotocatalysisNanotechnologyPlasmonSilver nanoparticleCatalysis
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Understanding light-driven H 2 evolution through the electronic tuning of aminopyridine cobalt complexes

2017

A new family of cobalt complexes with the general formula [CoII(OTf)2(Y,XPyMetacn)] (1R,Y,XPyMetacn ¼ 1-[(4-X-3,5-Y-2-pyridyl)methyl]-4,7-dimethyl-1,4,7-triazacyclononane, (X ¼ CN (1CN), CO2Et (1CO2Et), Cl (1Cl), H(1H), NMe2 (1NMe2)) where (Y ¼ H, and X ¼ OMe when Y ¼ Me (1DMM)) is reported. We found that the electronic tuning of the Y,XPyMetacn ligand not only has an impact on the electronic and structural properties of the metal center, but also allows for a systematic water-reduction-catalytic control. In particular, the increase of the electron-withdrawing character of the pyridine moiety promotes a 20-fold enhancement of the catalytic outcome. By UV-Vis spectroscopy, luminescence quenc…

Funcional de densitat Teoria delQuenching (fluorescence)010405 organic chemistryLigandchemistry.chemical_elementGeneral Chemistry010402 general chemistry01 natural sciences54Catalysis3. Good health0104 chemical sciencesCatalysisCrystallographyCatàlisiCatalytic cyclechemistryUltrafast laser spectroscopyLuminescenceSpectroscopyCobaltDensity functionalsChemical Science
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A Metal-Free, Nonconjugated Polymer for Solar Photocatalysis

2017

Heterogeneous catalysts that can absorb light over the solar range are ideal for green photocatalysis. Recently, attention has been directed towards the generation of novel solar-light photocatalysts, in particular, metal-free polymers. Herein, it is demonstrated that a metal-free, nonconjugated, anthraquinone-based copolymer (poly[1,4-diamine-9,10-dioxoanthracene-alt-(benzene-1,4-dioic acid)] (COP)) with a strong absorption in the visible region is effective as a sunlight heterogeneous photocatalyst. As a proof of concept, it has been used to mineralize 2,5-dichlorophenol (2,5-DCP) in water under air and sunlight irradiation. The photocatalytic efficiency of COP compares well with that of …

chemistry.chemical_classificationChemistryOrganic ChemistryNanotechnology02 engineering and technologyGeneral ChemistryPolymer010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistry01 natural sciencesFluorescenceAnthraquinoneCatalysis0104 chemical sciencesCatalysischemistry.chemical_compoundExcited stateUltrafast laser spectroscopyPhotocatalysis0210 nano-technologyAbsorption (electromagnetic radiation)Chemistry - A European Journal
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Insights into the Mechanism of Cumene Peroxidation Using Supported Gold and Silver Nanoparticles

2013

Due to the considerable industrial implications, an in-depth study of cumene peroxidation using supported gold and silver nanoparticles was carried out to gain more insight into the mechanism of this reaction. Supported gold nanoparticles were found to efficiently catalyze the decomposition of cumene hydroperoxide with a selectivity of 25% at 80 °C when using gold supported on hydrotalcite (AuNP@HT), and 2-phenyl-2-propanol (i.e., cumyl alcohol) was the main product. Further, silver nanoparticles supported on hydrotalcite (AgNP@HT) converted cumene to cumene hydroperoxide at 80 °C with 80% selectivity. Both benchtop and oxygen-uptake experiments were used to probe the reaction mechanism and…

CumeneReaction mechanismHydrotalcite010405 organic chemistryChemistryGeneral Chemistry010402 general chemistryPhotochemistry01 natural sciencesCatalysisSilver nanoparticle0104 chemical sciences3. Good healthCatalysischemistry.chemical_compoundCumene hydroperoxideColloidal goldSelectivityACS Catalysis
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Efficient Cementing of CH3NH3PbBr3Nanoparticles to Upconversion Nanoparticles Visualized by Confocal Microscopy

2016

Upconversion-perovskite nanohybrids are prepared by assembling CH3NH3PbBr3 perovskite nanoparticles (PK) with naked NaYF4:Yb3+,Tm3+ nanoparticles (UCn) via an innovative strategy consisting of using cucurbit[7]uril (CB[7]) to anchor the perovskite nanoparticles firmly and closely to the upconversion nanoparticles, thus leading to UCn@PKCB nanohybrids. A commercial multiphoton laser scanning confocal microscope is used to demonstrate the successful assembly. This technique proves to be useful to evaluate luminescence lifetime in the range of several tens of μs and allows visualization of the extraordinarily efficient nontrivial resonance energy transfer from the upconversion nanoparticle to …

PhotoluminescenceMicroscopeMaterials scienceNanostructureConfocalNanoparticleNanotechnology02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnologyCondensed Matter Physics01 natural sciences0104 chemical sciencesElectronic Optical and Magnetic Materialslaw.inventionBiomaterialsColloidConfocal microscopylawElectrochemistry0210 nano-technologyLuminescenceAdvanced Functional Materials
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Energy transfer in diiodoBodipy-grafted upconversion nanohybrids.

2015

Steady-state and time-resolved emission studies on nanohybrids consisting of NaYF4:Yb,Er and a diiodo-substituted Bodipy (UCNP-IBDP) show that the Yb(3+) metastable state, formed after absorption of a near-infrared (NIR) photon, can decay via two competitive energy transfer processes: sensitization of IBDP after absorption of a second NIR photon and population of Er(3+) excited states.

education.field_of_studyPhotonMaterials scienceEnergy transferPopulationPhysics::OpticsNanotechnologyAstrophysics::Cosmology and Extragalactic Astrophysics02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistry01 natural sciencesPhoton upconversion0104 chemical scienceschemistry.chemical_compoundchemistryExcited stateMetastabilityGeneral Materials ScienceBODIPY0210 nano-technologyAbsorption (electromagnetic radiation)educationAstrophysics::Galaxy AstrophysicsNanoscale
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Triggering the generation of an iron(IV)-oxo compound and its reactivity toward sulfides by RuII photocatalysis

2014

The preparation of [FeIV(O)(MePy2tacn)]2+ (2, MePy2tacn = N-methyl-N,N-bis(2-picolyl)-1,4,7-triazacyclononane) by reaction of [FeII(MePy2tacn)(solvent)]2+ (1) and PhIO in CH3CN and its full characterization are described. This compound can also be prepared photochemically from its iron(II) precursor by irradiation at 447 nm in the presence of catalytic amounts of [Ru II(bpy)3]2+ as photosensitizer and a sacrificial electron acceptor (Na2S2O8). Remarkably, the rate of the reaction of the photochemically prepared compound 2 toward sulfides increases 150-fold under irradiation, and 2 is partially regenerated after the sulfide has been consumed; hence, the process can be repeated several times.…

SulfideFotocatàlisi010402 general chemistryPhotochemistry01 natural sciencesBiochemistryChemical reactionArticleCatalysisCatalysisReaccions químiquesReaction rateColloid and Surface ChemistrySofre -- CompostosChemical reactionsSulphur compoundsOrganic chemistryWATER[CHIM.COOR]Chemical Sciences/Coordination chemistryPhotosensitizerReactivity (chemistry)Photocatalysischemistry.chemical_classificationOXYGENATION REACTIONS010405 organic chemistryChemistryGeneral ChemistryElectron acceptorSTATE0104 chemical sciencesELECTRON-TRANSFER PROPERTIESC-H OXIDATIONSPIN FE(IV) COMPLEXPhotocatalysisIRON-OXO COMPLEXESLIGANDTAURINE/ALPHA-KETOGLUTARATE DIOXYGENASENONHEME OXOIRON(IV) COMPLEXES
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Epoxidation of stilbene using supported gold nanoparticles: cumyl peroxyl radical activation at the gold nanoparticle surface.

2014

The catalytic epoxidation of cis-stilbene using cumene as a solvent in the presence of supported gold nanoparticles (AuNP) yields a mixture of cis and trans-stilbene oxides. EPR and product distribution studies support a new mechanistic proposal where oxygen centred radicals activate the AuNP surface and form active surface oxygen species responsible for the epoxidation products.

CumeneChemistryRadicalMetals and AlloysNanoparticleGeneral ChemistryPhotochemistryCatalysisProduct distribution3. Good healthSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialslaw.inventionCatalysisSolventchemistry.chemical_compoundlawColloidal goldMaterials ChemistryCeramics and CompositesElectron paramagnetic resonanceChemical communications (Cambridge, England)
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Functional Nanohybrids Based on Dyes and Upconversion Nanoparticles

2020

Upconversion nanoparticles (UCNPs) and dyes are combined to make nanohybrid systems, which take advantage of the synergic relationship between lanthanide (Ln)-based UCNPs and dyes. Ln-UCNPs are inorganic nanophosphors which absorb NIR light and emit narrow emission bands in the UV-NIR region with long luminescence lifetimes. These unique properties, when coordinated properly with dyes of the appropriate photophysical features, produce nanosystems with new photophysical properties. In this context, the UCNP-dye nanohybrids are very promising for potential sensing (ions and biomolecules) and theragnosis (imaging and therapy, e.g. photodynamic therapy).

chemistry.chemical_classificationLanthanideUpconversion nanoparticlesMaterials scienceNir lightchemistryBiomoleculemedicine.medical_treatmentmedicineContext (language use)NanotechnologyPhotodynamic therapyLuminescence
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CCDC 1578287: Experimental Crystal Structure Determination

2018

Related Article: Arnau Call, Federico Franco, Noufal Kandoth, Sergio Fernández, María González-Béjar, Julia Pérez-Prieto, Josep M. Luis, Julio Lloret-Fillol|2018|Chemical Science|9|2609|doi:10.1039/C7SC04328G

Space GroupCrystallographyCrystal SystemCrystal Structure{2-[(47-dimethyl-147-triazonan-1-yl)methyl]-NN-dimethylpyridin-4-amine}-bis(trifluoromethanesulfonato)-cobalt(ii)Cell ParametersExperimental 3D Coordinates
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CCDC 1578289: Experimental Crystal Structure Determination

2018

Related Article: Arnau Call, Federico Franco, Noufal Kandoth, Sergio Fernández, María González-Béjar, Julia Pérez-Prieto, Josep M. Luis, Julio Lloret-Fillol|2018|Chemical Science|9|2609|doi:10.1039/C7SC04328G

Space GroupCrystallographyCrystal SystemCrystal StructureCell Parameters{14-dimethyl-7-[(pyridin-2-yl)methyl]-147-triazonane}-bis(trifluoromethanesulfonato)-cobalt(ii)Experimental 3D Coordinates
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CCDC 1578286: Experimental Crystal Structure Determination

2018

Related Article: Arnau Call, Federico Franco, Noufal Kandoth, Sergio Fernández, María González-Béjar, Julia Pérez-Prieto, Josep M. Luis, Julio Lloret-Fillol|2018|Chemical Science|9|2609|doi:10.1039/C7SC04328G

Space GroupCrystallography{ethyl 2-[(47-dimethyl-147-triazonan-1-yl)methyl]pyridine-4-carboxylate}-bis(trifluoromethanesulfonato)-cobalt(ii)Crystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates
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CCDC 1003098: Experimental Crystal Structure Determination

2014

Related Article: Anna Company , Gerard Sabenya , María González-Béjar , Laura Gómez , Martin Clémancey , Geneviève Blondin , Andrew J. Jasniewski , Mayank Puri , Wesley R. Browne , Jean-Marc Latour , Lawrence Que Junior, Miquel Costas , Julia Pérez-Prieto, and Julio Lloret-Fillol|2014|J.Am.Chem.Soc.|136|4624|doi:10.1021/ja412059c

Space GroupCrystallographyCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates(acetonitrile)-(1-methyl-47-bis((pyridin-2-yl)methyl)-147-triazonane)-iron bis(trifluoromethanesulfonate)
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CCDC 1578285: Experimental Crystal Structure Determination

2018

Related Article: Arnau Call, Federico Franco, Noufal Kandoth, Sergio Fernández, María González-Béjar, Julia Pérez-Prieto, Josep M. Luis, Julio Lloret-Fillol|2018|Chemical Science|9|2609|doi:10.1039/C7SC04328G

bis(acetonitrile)-{2-[(47-dimethyl-147-triazonan-1-yl)methyl]pyridine-4-carbonitrile}-cobalt(ii) bis(trifluoromethanesulfonate)Space GroupCrystallographyCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates
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CCDC 1578284: Experimental Crystal Structure Determination

2018

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{1-[(4-chloropyridin-2-yl)methyl]-47-dimethyl-147-triazonane}-bis(trifluoromethanesulfonato)-cobalt(ii)Space GroupCrystallographyCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates
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CCDC 1578288: Experimental Crystal Structure Determination

2018

Related Article: Arnau Call, Federico Franco, Noufal Kandoth, Sergio Fernández, María González-Béjar, Julia Pérez-Prieto, Josep M. Luis, Julio Lloret-Fillol|2018|Chemical Science|9|2609|doi:10.1039/C7SC04328G

{1-[(4-methoxy-35-dimethylpyridin-2-yl)methyl]-47-dimethyl-147-triazonane}-bis(trifluoromethanesulfonato)-cobalt(ii)Space GroupCrystallographyCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates
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