Lanthanide-doped upconversion (UC) luminescent materials display multicolor emissions, making them ideal for a variety of applications, such as multi-channel biological imaging, fluorescence encryption, anti-counterfeiting, and 3D display. Manipulating the UC emissions of the luminescent materials with a fixed composition is crucial for their applications. Herein, we propose a facile strategy to achieve pulse-width-dependent multicolor UC emissions in NaYF4:Yb/Er/Tm nanocrystals. Upon excitation with a 980 nm continuous-wave laser diode, Er3+ ions in NaYF4:20%Yb,15%Er,1%Tm nanocrystals exhibited UC emissions with a red-to-green (R/G) ratio of 11.3. Nevertheless, by employing a 980 nm pulse laser with pulse widths from 0.1 to 10 ms, the UC R/G ratio can be easily adjusted from 0.9 to 11.3, resulting in continuous and remarkable color transformation from green, yellow, orange, to red. By virtue of the dynamic luminescence color variation of these NaYF4:20%Yb,15%Er,1%Tm nanocrystals, we demonstrated their potential applications in the areas of anti-counterfeiting and information encryption. These findings provide deep insights into the excited-state dynamics and energy transfer of Er3+ in NaYF4:Yb/Er/Tm nanocrystals upon 980 nm pulse excitation, which may pave the way for designing multicolor UC materials toward versatile applications.

1.
Y.
Liang
,
Z.
Zhu
,
S.
Qiao
,
X.
Guo
,
R.
Pu
,
H.
Tang
,
H.
Liu
,
H.
Dong
,
T.
Peng
,
L. D.
Sun
,
J.
Widengren
, and
Q.
Zhan
, “
Migrating photon avalanche in different emitters at the nanoscale enables 46th-order optical nonlinearity
,”
Nat. Nanotechnol.
17
,
524
(
2022
).
2.
S.
Liu
,
L.
Yan
,
J.
Huang
,
Q.
Zhang
, and
B.
Zhou
, “
Controlling upconversion in emerging multilayer core–shell nanostructures: From fundamentals to Frontier applications
,”
Chem. Soc. Rev.
51
,
1729
(
2022
).
3.
D.
Yang
,
P.
Ma
,
Z.
Hou
,
Z.
Cheng
,
C.
Li
, and
J.
Lin
, “
Current advances in lanthanide ion (Ln3+)-based upconversion nanomaterials for drug delivery
,”
Chem. Soc. Rev.
44
,
1416
(
2015
).
4.
B.
Ding
,
J.
Sheng
,
P.
Zheng
,
C.
Li
,
D.
Li
,
Z.
Cheng
,
P.
Ma
, and
J.
Lin
, “
Biodegradable upconversion nanoparticles induce pyroptosis for cancer immunotherapy
,”
Nano Lett.
21
,
8281
(
2021
).
5.
M. H.
Chan
and
R. S.
Liu
, “
Advanced sensing, imaging, and therapy nanoplatforms based on Nd3+-doped nanoparticle composites exhibiting upconversion induced by 808 nm near-infrared light
,”
Nanoscale
9
,
18153
(
2017
).
6.
M.
Kim
,
Y.
Kim
,
K.
Kim
,
W. T.
Huang
,
R. S.
Liu
,
J.
Hyun
, and
D.
Kim
, “
Gap surface plasmon-enhanced photoluminescence from upconversion nanoparticle-sensitized perovskite quantum dots in a metal–insulator–metal configuration under NIR excitation
,”
J. Mater. Chem. C
10
,
532
(
2022
).
7.
Y.
Wang
,
F.
Gao
,
S.
Zhou
,
P.
Hu
, and
J.
Fu
, “
Novel strategy for energy transfer via Ho3+ as a bridge in upconversion nanoparticles
,”
Sci. China Mater.
66
,
3696
(
2024
).
8.
T.
Sun
,
B.
Chen
,
Y.
Guo
,
Q.
Zhu
,
J.
Zhao
,
Y.
Li
,
X.
Chen
,
Y.
Wu
,
Y.
Gao
,
L.
Jin
,
S. T.
Chu
, and
F.
Wang
, “
Ultralarge anti-Stokes lasing through tandem upconversion
,”
Nat. Commun.
13
,
1032
(
2022
).
9.
H.
Bae
,
D.
Park
,
K.
Shin
,
H.
Lee
,
K. M.
Ok
, and
K.
Lee
, “
Upconversion properties in lanthanide doped layered-perovskite, CsBiNb2O7
,”
J. Chem. Phys.
154
,
054701
(
2021
).
10.
Z.
Chen
,
Z.
Cai
,
W.
Liu
, and
Z.
Yan
, “
Optical trapping and manipulation for single-particle spectroscopy and microscopy
,”
J. Chem. Phys.
157
,
050901
(
2022
).
11.
Y.
Li
,
W.
You
,
J.
Zhao
,
X.
Zhang
,
G.
Pan
,
P.
Liu
, and
Y.
Mao
, “
Unique excitation power density and pulse width-dependent multicolor upconversion emissions of Y2Mo4O15:Yb3+, Ho3+ for anti-counterfeiting and information encryption applications
,”
J. Mater. Chem. C
11
,
546
(
2023
).
12.
W.
You
,
X.
Zhang
,
R.
Yu
,
C.
Chen
,
M.
Li
,
G.
Pan
, and
Y.
Mao
, “
Highly efficient upconversion luminescence in narrow-bandgap Y2Mo4O15
,”
Opt. Lett.
49
,
1824
(
2024
).
13.
H.
Chen
,
Z.
Wu
,
J.
Ke
,
G.
Li
,
F.
Jiang
,
Y.
Liu
, and
M.
Hong
, “
Fabricating ultralow-power-excitable lanthanide-doped inorganic nanoparticles with anomalous thermo-enhanced photoluminescence behavior
,”
Sci. China Mater.
65
,
2793
(
2022
).
14.
M.
You
,
M.
Lin
,
S.
Wang
,
X.
Wang
,
G.
Zhang
,
Y.
Hong
,
Y.
Dong
,
G.
Jin
, and
F.
Xu
, “
Three-dimensional quick response code based on inkjet printing of upconversion fluorescent nanoparticles for drug anti-counterfeiting
,”
Nanoscale
8
,
10096
(
2016
).
15.
W.
Yao
,
Q.
Tian
,
J.
Liu
,
Q.
Xue
,
M.
Li
,
L.
Liu
,
Q.
Lu
, and
W.
Wu
, “
Preparation and RGB upconversion optic properties of transparent anti-counterfeiting films
,”
Nanoscale
9
,
15982
(
2017
).
16.
Y.
Han
,
H.
Li
,
Y.
Wang
,
Y.
Pan
,
L.
Huang
,
F.
Song
, and
W.
Huang
, “
Upconversion modulation through pulsed laser excitation for anti-counterfeiting
,”
Sci. Rep.
7
,
1320
(
2017
).
17.
J.
Zhou
,
Z.
Liu
, and
F.
Li
, “
Upconversion nanophosphors for small-animal imaging
,”
Chem. Soc. Rev.
41
,
1323
(
2012
).
18.
F.
Wang
,
D.
Banerjee
,
Y.
Liu
,
X.
Chen
, and
X.
Liu
, “
Upconversion nanoparticles in biological labeling, imaging, and therapy
,”
Analyst
135
,
1839
(
2010
).
19.
H.
Li
,
M.
Tan
,
X.
Wang
,
F.
Li
,
Y.
Zhang
,
L.
Zhao
,
C.
Yang
, and
G.
Chen
, “
Temporal multiplexed in vivo upconversion imaging
,”
J. Am. Chem. Soc.
142
,
2023
(
2020
).
20.
W.
Zheng
,
P.
Huang
,
D.
Tu
,
E.
Ma
,
H.
Zhu
, and
X.
Chen
, “
Lanthanide-doped upconversion nano-bioprobes: Electronic structures, optical properties, and biodetection
,”
Chem. Soc. Rev.
44
,
1379
(
2015
).
21.
F.
Wang
and
X.
Liu
, “
Upconversion multicolor fine-tuning: Visible to near-infrared emission from lanthanide-doped NaYF4 nanoparticles
,”
J. Am. Chem. Soc.
130
,
5642
(
2008
).
22.
F.
Wang
,
R.
Deng
,
J.
Wang
,
Q.
Wang
,
Y.
Han
,
H.
Zhu
,
X.
Chen
, and
X.
Liu
, “
Tuning upconversion through energy migration in core–shell nanoparticles
,”
Nat. Mater.
10
,
968
(
2011
).
23.
N. J.
Johnson
,
S.
He
,
S.
Diao
,
E. M.
Chan
,
H.
Dai
, and
A.
Almutairi
, “
Direct evidence for coupled surface and concentration quenching dynamics in lanthanide-doped nanocrystals
,”
J. Am. Chem. Soc.
139
,
3275
(
2017
).
24.
S.
Han
,
X.
Qin
,
Z.
An
,
Y.
Zhu
,
L.
Liang
,
Y.
Han
,
W.
Huang
, and
X.
Liu
, “
Multicolour synthesis in lanthanide-doped nanocrystals through cation exchange in water
,”
Nat. Commun.
7
,
13059
(
2016
).
25.
J.
Tang
,
L.
Chen
,
J.
Li
,
Z.
Wang
,
J.
Zhang
,
L.
Zhang
,
Y.
Luo
, and
X.
Wang
, “
Selectively enhanced red upconversion luminescence and phase/size manipulation via Fe3+ doping in NaYF4:Yb,Er nanocrystals
,”
Nanoscale
7
,
14752
(
2015
).
26.
D.
Chen
,
L.
Liu
,
P.
Huang
,
M.
Ding
,
J.
Zhong
, and
Z.
Ji
, “
Nd3+-sensitized Ho3+ single-band red upconversion luminescence in core–shell nanoarchitecture
,”
J. Phys. Chem. Lett.
6
,
2833
(
2015
).
27.
R. S. Y.
Monika
,
R. S.
Yadav
,
A.
Bahadur
, and
S. B.
Rai
, “
Near-infrared light excited highly pure green upconversion photoluminescence and intrinsic optical bistability sensing in a Ho3+/Yb3+ co-doped ZnGa2O4 phosphor through Li+ doping
,”
J. Phys. Chem. C
124
,
10117
(
2020
).
28.
J.
Wang
,
F.
Wang
,
C.
Wang
,
Z.
Liu
, and
X.
Liu
, “
Single-band upconversion emission in lanthanide-doped KMnF3 nanocrystals
,”
Angew. Chem., Int. Ed.
50
,
10369
(
2011
).
29.
H.
Zou
,
B.
Chen
,
Y.
Hu
,
Q.
Zhang
,
X.
Wang
, and
F.
Wang
, “
Simultaneous enhancement and modulation of upconversion by thermal stimulation in Sc2Mo3O12 crystals
,”
J. Phys. Chem. Lett.
11
,
3020
(
2020
).
30.
Q.
Shao
,
G.
Zhang
,
L.
Ouyang
,
Y.
Hu
,
Y.
Dong
, and
J.
Jiang
, “
Emission color tuning of core/shell upconversion nanoparticles through modulation of laser power or temperature
,”
Nanoscale
9
,
12132
(
2017
).
31.
Y.
Hu
,
Q.
Shao
,
X.
Deng
,
D.
Song
,
S.
Han
,
Y.
Dong
, and
J.
Jiang
, “
Thermally induced multicolor emissions of upconversion hybrids with large color shifts for anticounterfeiting applications
,”
J. Mater. Chem. C
7
,
11770
(
2019
).
32.
J.
Zhu
,
S.
Wang
,
Z.
Yang
,
S.
Liao
,
J.
Lin
,
H.
Yao
,
F.
Huang
,
Y.
Zheng
, and
D.
Chen
, “
A single-beam NIR laser-triggered full-color upconversion tuning of a Er/Tm:CsYb2F7@glass photothermal nanocomposite for optical security
,”
Nanoscale
14
,
3407
(
2022
).
33.
J.
Zhou
,
S.
Wen
,
J.
Liao
,
C.
Clarke
,
S. A.
Tawfik
,
W.
Ren
,
C.
Mi
,
F.
Wang
, and
D.
Jin
, “
Activation of the surface dark-layer to enhance upconversion in a thermal field
,”
Nat. Photonics
12
,
154
(
2018
).
34.
B.
Chen
,
Y.
Liu
,
Y.
Xiao
,
X.
Chen
,
Y.
Li
,
M.
Li
,
X.
Qiao
,
X.
Fan
, and
F.
Wang
, “
Amplifying excitation-power sensitivity of photon upconversion in a NaYbF4:Ho nanostructure for direct visualization of electromagnetic hotspots
,”
J. Phys. Chem. Lett.
7
,
4916
(
2016
).
35.
W.
You
,
D.
Tu
,
R.
Li
,
W.
Zheng
, and
X.
Chen
, “
Chameleon-like optical behavior of lanthanide-doped fluoride nanoplates for multilevel anti-counterfeiting applications
,”
Nano Res.
12
,
1417
(
2019
).
36.
X.
Li
,
Z.
Guo
,
T.
Zhao
,
Y.
Lu
,
L.
Zhou
,
D.
Zhao
, and
F.
Zhang
, “
Filtration shell mediated power density independent orthogonal excitations–emissions upconversion luminescence
,”
Angew. Chem., Int. Ed.
55
,
2464
(
2016
).
37.
Z.
Zhang
and
Y.
Zhang
, “
Orthogonal emissive upconversion nanoparticles: Material design and applications
,”
Small
17
,
e2004552
(
2021
).
38.
H.
Dong
,
L. D.
Sun
,
W.
Feng
,
Y.
Gu
,
F.
Li
, and
C. H.
Yan
, “
Versatile spectral and lifetime multiplexing nanoplatform with excitation orthogonalized upconversion luminescence
,”
ACS Nano
11
,
3289
(
2017
).
39.
R.
Deng
,
F.
Qin
,
R.
Chen
,
W.
Huang
,
M.
Hong
, and
X.
Liu
, “
Temporal full-colour tuning through non-steady-state upconversion
,”
Nat. Nanotechnol.
10
,
237
(
2015
).
40.
Z.
An
,
Q.
Li
,
J.
Huang
,
L.
Tao
, and
B.
Zhou
, “
Selectively manipulating interactions between lanthanide sublattices in nanostructure toward orthogonal upconversion
,”
Nano Lett.
23
,
6241
(
2023
).
41.
J.
Huang
,
Z.
An
,
L.
Yan
, and
B.
Zhou
, “
Engineering orthogonal upconversion through selective excitation in a single nanoparticle
,”
Adv. Funct. Mater.
33
,
2212037
(
2023
).
You do not currently have access to this content.