Plasmonic interactions of gold nanoparticles with photoluminescent materials
Notice bibliographique
Résumé
The variable plasmonic resonances of metal nanoparticles have many applications across a wide range of fields, including the modification of the emission of photoluminescent materials. The plasmonic interactions of gold nanoparticles with two types of photoluminescent nanoparticles are explored. Plasmonic gold nanoparticles are synthesised: nanorods, bipyramids, and nanostars. The concentration of the reagents used in their syntheses are varied to produce nanoparticles with both sharp and broad plasmon resonances across the visible and near infrared spectrum, from 600 nm to above 1100 nm. The particles are also simulated, to observe the electric field enhancements of each particle type. A full investigation into the effect of varying the concentration of the reducing agent, l-ascorbic acid, in the synthesis of bipyramids is carried out. A nonlinear dependence is found, with a sharp increase at lower l-ascorbic acid concentrations and a plateau at higher concentrations, likely due to the change in ratio between l-ascorbic acid and HAuCl4. Bipyramids with plasmon resonance wavelengths longer than 1000 nm are synthesised without the use of a regrowth step or reducing seed concentration, but by only varying AA concentration, which has not been previously achieved in the literature. Using the high electric field enhancements and small mode volume of the gold bipyramids, plasmon-induced two-photon polymerisation is shown. Polymerisation is demonstrated at powers far below the threshold typically required, as the bipyramids enhance the electric field of incoming laser light. A linear relationship between polymerised area (visible from SEM) and applied laser power is discovered, further corroborating this enhancement as the polymerised area depends on the electric field strength. This enhanced polymerisation allows for spatial confinement of quantum dots. When quantum dots are added to the monomer, they remain wherever the solution is polymerised, and all other quantum dots are removed. They are trapped at the location of highest field enhancement, by design, and thus also interact with the plasmonic bipyramid. This provides a novel fabrication method for bipyramid-quantum dot pairs, with quantum dots preferentially confined at one tip of a bipyramid. The localisation of the quantum dots in this high field enhancement area results in emission rate enhancement and even strong coupling between the quantum dots and bipyramids, shown by Rabi splitting in the bipyramid scattering spectra. Upconverting nanoparticles of various sizes, dopants, and emission wavelengths are synthesised. The dopants, Yb3+, Er3+ and Tm3+, give emission wavelengths from 450-800 nm and the sizes obtained by varying synthesis reaction volume and the speed of injecting the nucleation solution were between ? 5-40 nm. Layer-by-layer deposition of these particles is carried out, resulting in samples with even and consistent upconversion emission. These are topped with polyelectrolyte spacer layers followed by nanostars, nanorods and bipyramids, resulting in enhancement by nanorods and bipyramids, with bipyramid enhancement of up to 7.5x, the first time such enhancement has been demonstrated. In order to create samples with higher plasmonic nanoparticle concentrations, spin-coating is employed. Multiresonant gold nanostars, coated with silica shells as spacers, are spin-coated atop upconverting nanoparticle layers. Samples with high nanostar concentration demonstrate enhancement, with nanostar clusters showing enhancement of up to 9.7x. This high enhancement value likely occurs due to plasmonic hotspots between the nanostars, and could have applications in the enhancement of upconverting nanoparticle emission for use in solar cell efficiency improvement.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,002 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,001 |
| Méta-épidémiologie (sens large) | 0,001 | 0,000 |
| Bibliométrie | 0,003 | 0,004 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,002 | 0,000 |
| Science ouverte | 0,002 | 0,001 |
| Intégrité de la recherche | 0,000 | 0,002 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,077 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; les deux têtes enseignantes s’accordent sur ce qui est montré ici.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».