Explaining the influence of dopant concentration and excitation power density on the luminescence and brightness of β-NaYF4:Yb3+,Er3+ nanoparticles: Measurements and simulations
- We assessed the influence of Yb3+ and Er3+ dopant concentration on the relative spectral distribution, quantum yield ( UC), and decay kinetics of the upconversion luminescence (UCL) and particle brightness (BUC) for similarly sized (33 nm) oleate-capped -NaYF4:Yb3+,Er3+ upconversion (UC) nanoparticles (UCNPs) in toluene at broadly varied excitation power densities (P). This included an Yb3+ series where the Yb3+ concentration was varied between 11%–21% for a constant Er3+ concentration of 3%, and an Er3+ series, where the Er3+ concentration was varied between 1%–4% for a constant Yb3+ concentration of 14%. The results were fitted with a coupled rate equation model utilizing the UCL data and decay kinetics of the green and red Er3+ emission and the Yb3+ luminescence at 980 nm. An increasing Yb3+ concentration favors a pronounced triphotonic population of 4F9/2 at high P by an enhanced back energy transfer (BET) from the 4G11/2 level. Simultaneously, the Yb3+-controlled UCNPsWe assessed the influence of Yb3+ and Er3+ dopant concentration on the relative spectral distribution, quantum yield ( UC), and decay kinetics of the upconversion luminescence (UCL) and particle brightness (BUC) for similarly sized (33 nm) oleate-capped -NaYF4:Yb3+,Er3+ upconversion (UC) nanoparticles (UCNPs) in toluene at broadly varied excitation power densities (P). This included an Yb3+ series where the Yb3+ concentration was varied between 11%–21% for a constant Er3+ concentration of 3%, and an Er3+ series, where the Er3+ concentration was varied between 1%–4% for a constant Yb3+ concentration of 14%. The results were fitted with a coupled rate equation model utilizing the UCL data and decay kinetics of the green and red Er3+ emission and the Yb3+ luminescence at 980 nm. An increasing Yb3+ concentration favors a pronounced triphotonic population of 4F9/2 at high P by an enhanced back energy transfer (BET) from the 4G11/2 level. Simultaneously, the Yb3+-controlled UCNPs absorption cross section overcompensates for the reduction in UC with increasing Yb3+ concentration at high P, resulting in an increase in BUC. Additionally, our results show that an increase in Yb3+ and a decrease in Er3+ concentration enhance the color tuning range by P. These findings will pave the road to a deeper understanding of the energy transfer processes and their contribution to efficient UCL, as well as still debated trends in green-to-red intensity ratios of UCNPs at different P.…
Autor*innen: | Ute Resch-GengerORCiD |
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Persönliche Herausgeber*innen: | Martin Kaiser, Christian WürthORCiD, Marco Kraft, T. Soukka |
Dokumenttyp: | Zeitschriftenartikel |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | Nano Research |
Jahr der Erstveröffentlichung: | 2019 |
Organisationseinheit der BAM: | 1 Analytische Chemie; Referenzmaterialien |
1 Analytische Chemie; Referenzmaterialien / 1.2 Biophotonik | |
Verlag: | Springer |
Jahrgang/Band: | 12 |
Ausgabe/Heft: | 8 |
Erste Seite: | 1871 |
Letzte Seite: | 1879 |
DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
Freie Schlagwörter: | Absolute measurement; Energy transfer; Er(III); Fluorescence; Integration sphere spectroscopy; Lanthanide; Lifetime, synthesis; Mechanism; Nanoparticle; Quantum yield; Surface chemistry; Upconversion nanoparticle; Yb(III) |
Themenfelder/Aktivitätsfelder der BAM: | Chemie und Prozesstechnik |
DOI: | 10.1007/s12274-019-2450-4 |
ISSN: | 1998-0124 |
ISSN: | 1998-0000 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 09.09.2019 |
Referierte Publikation: | Ja |
Datum der Eintragung als referierte Publikation: | 09.09.2019 |