TY - JOUR
T1 - Bright Infrared-to-Ultraviolet/Visible Upconversion in Small Alkaline Earth-Based Nanoparticles with Biocompatible CaF2 Shells
AU - Fischer, Stefan
AU - Siefe, Chris
AU - Swearer, Dayne F.
AU - McLellan, Claire A.
AU - Alivisatos, A. Paul
AU - Dionne, Jennifer A.
N1 - Funding Information:
S.F., C.S., and J.A.D. acknowledge support from the Photonics at Thermodynamic limits Energy Frontier Research Center, funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award No. DE‐SC0019140. C.S. was supported by an Eastman Kodak fellowship, NIH Grant 5R21GM129879‐02, and NIH Grant 1DP2AI15207201. D.F.S acknowledges support from the Arnold and Mabel Beckman Foundation with a Postdoctoral Fellowship in the Chemical Sciences. C.A.M. and J.A.D. acknowledge financial support from the Stanford Bio‐X Interdisciplinary Initiatives Committee (IIP) and NIH Grant 5R21GM129879‐02. C.A.M. was supported by the Wu Tsai Neurosciences Institute and also received support from NIH Grant 1DP2AI15207201. TEM imaging was performed at the Stanford Nano Shared Facilities (SNSF), supported by the National Science Foundation under Award ECCS‐1542152.
Funding Information:
S.F., C.S., and J.A.D. acknowledge support from the Photonics at Thermodynamic limits Energy Frontier Research Center, funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award No. DE-SC0019140. C.S. was supported by an Eastman Kodak fellowship, NIH Grant 5R21GM129879-02, and NIH Grant 1DP2AI15207201. D.F.S acknowledges support from the Arnold and Mabel Beckman Foundation with a Postdoctoral Fellowship in the Chemical Sciences. C.A.M. and J.A.D. acknowledge financial support from the Stanford Bio-X Interdisciplinary Initiatives Committee (IIP) and NIH Grant 5R21GM129879-02. C.A.M. was supported by the Wu Tsai Neurosciences Institute and also received support from NIH Grant 1DP2AI15207201. TEM imaging was performed at the Stanford Nano Shared Facilities (SNSF), supported by the National Science Foundation under Award ECCS-1542152.
Publisher Copyright:
© 2020 Wiley-VCH GmbH
PY - 2020/11/23
Y1 - 2020/11/23
N2 - Upconverting nanoparticles (UCNPs) are promising candidates for photon-driven reactions, including light-triggered drug delivery, photodynamic therapy, and photocatalysis. Herein, we investigate the NIR-to-UV/visible emission of sub-15 nm alkaline-earth rare-earth fluoride UCNPs (M1−xLnxF2+x, MLnF) with a CaF2 shell. We synthesize 8 alkaline-earth host materials doped with Yb3+ and Tm3+, with alkaline-earth (M) spanning Ca, Sr, and Ba, MgSr, CaSr, CaBa, SrBa, and CaSrBa. We explore UCNP composition, size, and lanthanide doping-dependent emission, focusing on upconversion quantum yield (UCQY) and UV emission. UCQY values of 2.46 % at 250 W cm−2 are achieved with 14.5 nm SrLuF@CaF2 particles, with 7.3 % of total emission in the UV. In 10.9 nm SrYbF:1 %Tm3+@CaF2 particles, UV emission increased to 9.9 % with UCQY at 1.14 %. We demonstrate dye degradation under NIR illumination using SrYbF:1 %Tm3+@CaF2, highlighting the efficiency of these UCNPs and their ability to trigger photoprocesses.
AB - Upconverting nanoparticles (UCNPs) are promising candidates for photon-driven reactions, including light-triggered drug delivery, photodynamic therapy, and photocatalysis. Herein, we investigate the NIR-to-UV/visible emission of sub-15 nm alkaline-earth rare-earth fluoride UCNPs (M1−xLnxF2+x, MLnF) with a CaF2 shell. We synthesize 8 alkaline-earth host materials doped with Yb3+ and Tm3+, with alkaline-earth (M) spanning Ca, Sr, and Ba, MgSr, CaSr, CaBa, SrBa, and CaSrBa. We explore UCNP composition, size, and lanthanide doping-dependent emission, focusing on upconversion quantum yield (UCQY) and UV emission. UCQY values of 2.46 % at 250 W cm−2 are achieved with 14.5 nm SrLuF@CaF2 particles, with 7.3 % of total emission in the UV. In 10.9 nm SrYbF:1 %Tm3+@CaF2 particles, UV emission increased to 9.9 % with UCQY at 1.14 %. We demonstrate dye degradation under NIR illumination using SrYbF:1 %Tm3+@CaF2, highlighting the efficiency of these UCNPs and their ability to trigger photoprocesses.
KW - alkaline earth metals
KW - lanthanides
KW - nanoparticles
KW - photophysics
KW - upconversion
UR - http://www.scopus.com/inward/record.url?scp=85091307771&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85091307771&partnerID=8YFLogxK
U2 - 10.1002/anie.202007683
DO - 10.1002/anie.202007683
M3 - Article
C2 - 32841471
AN - SCOPUS:85091307771
SN - 1433-7851
VL - 59
SP - 21603
EP - 21612
JO - Angewandte Chemie - International Edition
JF - Angewandte Chemie - International Edition
IS - 48
ER -