In:
Journal of Materials Chemistry C, Royal Society of Chemistry (RSC), Vol. 11, No. 30 ( 2023), p. 10409-10419
Abstract:
High-power density applications using up-conversion (UC) systems rely mostly on the Yb, Tm lanthanide couple. Herein, we investigate the extent to which Gd high energy levels can enhance the four-order UC process in NaGdF 4 :Yb, Er under pulsed excitation, making the Yb, Er UC system suitable for high power density applications. Unlike cw excitation, pulsed laser excitation enables higher equivalent power densities with reduced local heating effects. We found that Gd upholds the saturation level by one order of magnitude in NaGdF 4 :Yb, Er@NaYF 4 compared to NaYF 4 :Yb, Er@NaYF 4 nanoparticles, i.e. , from 5 × 10 6 to 5 × 10 7 W cm −2 . Such an effect is determined by efficient two-step Er–Gd energy transfer, in which the Gd levels, populated by four-order Yb–Er processes, act further as the long(est)-lived reservoir level for Er UC emissions. Notably, above 10 8 W cm −2 , NaGdF 4 :Yb, Er@NaYF 4 shows similar performance to NaGdF 4 :Yb, Tm@NaYF 4 in terms of UC photon order, which is considered a direct indicator of spatial resolution in high power density applications. Our results showcase the promise of the Yb, (Gd) Er UC system for high power density applications, thus stimulating research for expanding the presently limited range of applicable UC systems.
Type of Medium:
Online Resource
ISSN:
2050-7526
,
2050-7534
Language:
English
Publisher:
Royal Society of Chemistry (RSC)
Publication Date:
2023
detail.hit.zdb_id:
2702245-6
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