Search results for " nanocrystals"

showing 10 items of 39 documents

Core‐Selective Silver‐Doping of Gold Nanoclusters by Surface‐Bound Sulphates on Colloidal Templates: From Synthetic Mechanism to Relaxation Dynamics

2022

Funding Information: This work was carried out under the ERC Advanced grant (DRIVEN, ERC‐2016‐AdG‐742829), Academy of Finland's Centre of Excellence in Life‐Inspired Hybrid Materials (LIBER, 346108), Academy of Finland (No. 321443, 328942, 308647, and 318891) and Photonic Research and Innovation (PREIN) as well as FinnCERES flagships. L.F. and X.C. thanks for support from CSC (IT Center for Science, Finland) for providing computation resources. The authors acknowledge the provision of facilities and technical support by Aalto University OtaNano – Nanomicroscopy Center (Aalto‐NMC). | openaire: EC/H2020/742829/EU//DRIVEN Ultra-small luminescent gold nanoclusters (AuNCs) have gained substantia…

216 Materials engineeringSettore FIS/01 - Fisica Sperimentaletoxicityphotoluminescencedopinggold nanoclusterscellulose nanocrystalsAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsAdvanced Optical Materials
researchProduct

Influence of chitin nanocrystals on the dielectric behaviour and conductivity of chitosan-based bionanocomposites

2018

[EN] A series of bionanocomposite films based on chitosan, reinforced with chitin nanocrystals, were developed, and assessed in terms of dielectric behaviour and conductivity by using an experimental methodology that allows avoiding the conductivity contribution and the exclusion of contact and interfacial polarization effects. The dielectric relaxations at low and high frequency and temperatures were modeled by Havriliak-Negami functions. Below the glass transition temperature (Tg), the gamma and beta relaxations were observed, which were related to intramolecular and non-cooperative segmental movements. At higher temperatures, an intermolecular and cooperative macromolecular movement, rel…

BionanocompositesSolucions polimèriquesMaterials scienceMaterial testingIonic bonding02 engineering and technologyDielectricActivation energyConductivity010402 general chemistry01 natural sciencesChitosanchemistry.chemical_compoundElectrical resistivity and conductivity[CHIM.ANAL]Chemical Sciences/Analytical chemistryComposite materialsChitosanChitosanIntermolecular forceGeneral EngineeringINGENIERIA DE LOS PROCESOS DE FABRICACION[CHIM.MATE]Chemical Sciences/Material chemistryCiència dels materials021001 nanoscience & nanotechnology0104 chemical sciencesChitin nanocrystals[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry[CHIM.POLY]Chemical Sciences/PolymersChemical engineeringchemistryMAQUINAS Y MOTORES TERMICOSCeramics and CompositesChitin nanocrystal0210 nano-technologyGlass transitionDielectric thermal analysis (DETA)
researchProduct

Polysaccharide nanocrystals as fillers for PLA based nanocomposites

2016

The development of green nanocomposites based on biopolymers and bio-based nanofillers has attracted over the recent years the attention of academic and industrial research. Indeed, these nanocomposites could replace some oil-derived polymers and thus helping to overcome environmental problems. In this regard, PLA as matrix and polysaccharide nanocrystals as fillers are the most promising components to obtain high-performance green bio-nanocomposites suitable for different applications, particularly for packaging and biomedical applications. Indeed, at present, due to its processability, mechanical and biological properties, as well as its commercial availability, poly(lactic acid) (PLA) po…

Cellulose nanocrystals (CNCs)Materials sciencePolymers and PlasticsStarchNanotechnologyChitin nanocrystals (ChNCs)02 engineering and technology010402 general chemistryPolysaccharide01 natural sciencesPoly(lactic acid) (PLA)chemistry.chemical_compoundChitinCellulosePolysaccharide nanocrystalchemistry.chemical_classificationNanocompositeNanocompositePolymerBiodegradation021001 nanoscience & nanotechnologyStarch nanocrystals (SNCs)0104 chemical sciencesSettore ING-IND/22 - Scienza E Tecnologia Dei MaterialiNanocrystalchemistry0210 nano-technology
researchProduct

Synthesis, Characterization, and Spectroscopy of Type-II Core/Shell Semiconductor Nanocrystals with ZnTe Cores

2005

Core shellMaterials scienceChemical engineeringMechanics of MaterialsMechanical EngineeringSemiconductor nanocrystalsGeneral Materials ScienceSpectroscopyCharacterization (materials science)Advanced Materials
researchProduct

Controlled Synthesis of CdSe Tetrapods with High Morphological Uniformity by the Persistent Kinetic Growth and the Halide-Mediated Phase Transformati…

2012

We report scalable controlled synthesis of CdSe tetrapods with high morphological uniformity based on the continuous precursor injection (CPI) approach with halide ligands. The CPI approach involves the successive injection of precursors into the seed solution at a controlled rate so that the reaction condition remains in the kinetic growth regime. To initiate the successful development of tetrapod structure, the controlled amount of halide ligands are added during the reaction, which triggered the formation of wurtzite arms on {111}-facets of the zincblende seeds. The formation of the wurtzite phase is responsible for the halide-mediated displacement of oleate ligands, destabilizing the em…

CrystallographyCdse nanocrystalsKinetic growthHexagonal crystal systemChemistryGeneral Chemical EngineeringPhase (matter)Materials ChemistryHalideNanotechnologyGeneral ChemistryWurtzite crystal structureChemistry of Materials
researchProduct

Capacitive effects in silicon-supported polyoxometalate-based nanocrystals

2011

Dielectrics nanocrystals AFM Langmuir-Blodgett
researchProduct

Application of delta recycling to electron automated diffraction tomography data from inorganic crystalline nanovolumes

2013

δ Recycling is a simple procedure for directly extracting phase information from Patterson-type functions [Rius (2012). Acta Cryst. A68, 399-400]. This new phasing method has a clear theoretical basis and was developed with ideal single-crystal X-ray diffraction data. On the other hand, introduction of the automated diffraction tomography (ADT) technique has represented a significant advance in electron diffraction data collection [Kolb et al. (2007). Ultramicroscopy, 107, 507-513]. When combined with precession electron diffraction, it delivers quasi-kinematical intensity data even for complex inorganic compounds, so that single-crystal diffraction data of nanometric volumes are now availa…

Diffraction[delta] recycling; direct methods; structure solution; electron diffraction; automated diffraction tomography; nano electron diffraction; precession electron diffraction; nanocrystals.Reflection high-energy electron diffractionMaterials scienceGas electron diffractionAnalytical chemistrydirect methodsDiffraction tomographyprecession electron diffractionElectron diffractionnanocrystalsStructural BiologyDirect methodsstructure solutionautomated diffraction tomographynano electron diffractionPrecession electron diffractionelectron diffractionElectron backscatter diffraction[delta] recycling
researchProduct

Colloidal Nanoplatelet/Conducting Polymer Hybrids: Excitonic And Material Properties

2016

WOS:000370678700053 Here we present the first account of conductive polymer/colloidal nanoplatelet hybrids. For this, we developed DEH-PPV-based polymers with two different anchor groups (sulfide and amine) acting as surfactants for CdSe nanoplatelets, which are atomically flat semiconductor nanocrystals. Hybridization of the polymers with the nanoplatelets in the solution phase was observed to cause strong photoluminescence quenching in both materials. Through steady-state photoluminescence and excitation spectrum measurements, photoluminescence quenching was shown to result from dominant exciton dissociation through charge transfer at the polymer/nanoplatelet interfaces that possess a sta…

Excitation spectrumMaterials sciencePhotoluminescenceSulfideDEH-PPV-Based PolymersSulfideExcitonCdSe NanoplateletsNanotechnology02 engineering and technologySurface active agents010402 general chemistryOptoelectronic devices01 natural sciencesDissociation (chemistry)ColloidCharge transferQuenchingHybrid optoelectronic devicesPhysical and Theoretical ChemistryPhotoluminescenceSulfur compoundsAmineSemiconductor nanocrystalsConductive polymerchemistry.chemical_classificationExcited statesBuilding blockesPolymerInterface statesEmission quenching021001 nanoscience & nanotechnology0104 chemical sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsPolymer/Colloidal Nanoplatelet HybridsGeneral EnergyChemical engineeringchemistryExcited stateAnchorsExcitons0210 nano-technologyDissociationConductive polymerPhotoluminescence quenchingExciton dissociation
researchProduct

Optical Amplification in Hollow-Core Negative-Curvature Fibers Doped with Perovskite CsPbBr3 Nanocrystals

2019

| openaire: EC/H2020/820423/EU//S2QUIP We report a hollow-core negative-curvature fiber (HC-NCF) optical signal amplifier fabricated by the filling of the air microchannels of the fiber with all-inorganic CsPbBr3 perovskite nanocrystals (PNCs). The optimum fabrication conditions were found to enhance the optical gain, up to +3 dB in the best device. Experimental results were approximately reproduced by a gain assisted mechanism based on the nonlinear optical properties of the PNCs, indicating that signal regeneration can be achieved under low pump powers, much below the threshold of stimulated emission. The results can pave the road of new functionalities of the HC-NCF with PNCs, such as op…

FabricationMaterials scienceperovskite nanocrystalsGeneral Chemical Engineeringnonlinear optical properties02 engineering and technology01 natural scienceslcsh:Chemistry010309 opticssignal regeneration/amplification0103 physical sciencesGeneral Materials ScienceStimulated emissionFiberPerovskite (structure)business.industryDopingÒpticahollow core fibers021001 nanoscience & nanotechnologyNonlinear systemlcsh:QD1-999NanocrystalOptoelectronicsMaterials nanoestructurats0210 nano-technologybusinessSignal regenerationNanomaterials
researchProduct

Ion-Track Template Synthesis and Characterization of ZnSeO3 Nanocrystals

2022

A.I.P. thanks the Institute of Solid-State Physics, University of Latvia. ISSP UL as the Center of Excellence is supported through the Framework Program for European universities. The work was carried out within the framework of the grant AP05134367 of the Ministry Funding: The work was carried out within the framework of the grant AP05134367 of the Ministry of education and Science Science of of the Republic Republic of Kazakhstan.

Inorganic ChemistrySiO<sub>2</sub>/Si track template; chemical and electrochemical deposition; ZnSeO<sub>3</sub> nanocrystals; XRD study; quantum chemical calculationchemical and electrochemical depositionGeneral Chemical Engineering:NATURAL SCIENCES::Physics [Research Subject Categories]General Materials ScienceSiO2/Si track templateZnSeO3 nanocrystalsCondensed Matter Physicsquantum chemical calculationXRD studyCrystals
researchProduct