Article
Optics
Zhaoyu Ye, Ai-Hua Li
Summary: This paper conducts a simulation study on the optical properties of an elongated Ag semi-shell coated on a nanorod. It is found that the nondegenerate longitudinal and radial void modes in the Ag cavity can be independently and controllably tuned to resonate with excitation and emission. The elongated Ag semi-shell acts as an efficient dual-resonance plasmonic structure, achieving significant enhancement of green and red upconversion luminescence.
JOURNAL OF LUMINESCENCE
(2023)
Article
Materials Science, Ceramics
Nguyen Ba Tong, Le Van Si, Cao T. M. Dung, Ta Thi Kieu Hanh, Tran Thi Ngoc Lam, Phan Bach Thang, Do Huy Binh, Nguyen Thai Ngoc Uyen, Tran T. T. Van
Summary: This study successfully prepared hydrophilic pigments based on NaYF4:Er,Yb@SiO2 nanoparticles for water-based ink printing, which can be used for anti-counterfeiting printing, biological imaging, and optical information storage.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Ze Wang, Benfu Qian, Fangke Wang, Qianran Zhao, Yulu Wang, Haifeng Zou, Yanhua Song, Xiuqing Zhou, Ye Sheng
Summary: Uniform and well-dispersed SiO2:x%Tb3+@Lu2O3:y%Eu3+ core-shell spherical phosphors were successfully synthesized, demonstrating that multicolor luminescence could be achieved by changing the doping ratio of Eu3+ or excitation wavelengths. Coating the Lu2O3:Eu3+ layer uniformly on the surface of SiO2:Tb3+ spheres resulted in stronger luminescence intensity, longer fluorescence lifetime, and higher energy transfer efficiency. These results provide a new approach for enhancing luminescence and achieving multicolor luminescence.
INORGANIC CHEMISTRY
(2021)
Article
Materials Science, Multidisciplinary
Hanchen Shen, Kai Feng, Guangzhe Lu, Yoshio Sakka, Bin Lu
Summary: A series of phosphor particles doped with different concentrations of Yb3+ were studied, showing strong green and weak red emissions. The optimal concentrations of Yb3+ were determined to be 1.0 at% in oxide and 0.5 at% in oxysulfide, with the Lu2O2S:Er/Yb phosphor exhibiting significantly higher luminescence intensity.
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
(2021)
Article
Chemistry, Physical
Christian Wurth, Bettina Grauel, Monika Pons, Florian Frenzel, Philipp Rissiek, Kerstin Rucker, Markus Haase, Ute Resch-Genger
Summary: This study systematically analyzed the dependence of UC luminescence quantum yield on the dopant concentration in solid NaYF4:Yb,Er/NaYF4:Lu upconversion core/shell nanocrystals. The results showed that high Yb3+ concentrations can increase the particle absorption cross section and brightness of UCNC, while high Er3+ concentrations can decrease the luminescence brightness.
Article
Spectroscopy
Hongqi Chen, Wen Wang, Changchun Ji, Lun Wang
Summary: The water-solubility of core-shell upconversion nanoparticles was improved by a ligand exchange reaction; a sensing system for detection of H2S was successfully constructed with a wide linear detection range and low detection limit; the dye-sensitized nanoprobe showed satisfactory performance in real sample analysis.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)
Article
Optics
Peng LI, Zhen Zhang, Ziyi Xu, Haiqin Sun, Qiwei Zhang, Xihong Hao
Summary: In this study, a novel strategy is proposed to enhance the low-temperature sensing properties by controlling the photochromic reaction process in Na0.5Bi2.5Ta2O9: Er/Yb samples. The maximum relative sensitivity reaches up to 5.99% K-1 at cryogenic temperature of 153 K, and after irradiation with a commercial laser of 405 nm for 30 s, the relative sensitivity is increased to 6.81% K-1. The improvement is attributed to the coupling of optical thermometric and photochromic behavior at elevated temperatures, offering a new avenue to improve the thermometric sensitivity in photo-stimuli response photochromic materials.
Article
Materials Science, Ceramics
Jie Chen, Yixin Gao, Chao Wang, Yu Yin, Jiaxing Song, Xiaodan Zeng, Zhigang Liu, Haifeng Jiang
Summary: In this study, NaErF4 crystals with diverse crystal phases and morphologies were prepared using a simple hydrothermal method, and a series of NaErF4@SiO2 core-shell samples with different SiO2 shell thickness were successfully prepared. It was found that increasing the F- content can enhance the upconversion luminescence intensity of NaErF4, and changing the NaErF4 crystal phase and SiO2 shell thickness can bring about multicolor luminescence. Additionally, the NaErF4 and NaErF4@SiO2 samples showed a greater red to green ratio compared to traditional co-doping systems, suggesting potential applications in biological imaging and sensing fields.
CERAMICS INTERNATIONAL
(2022)
Article
Chemistry, Physical
Shaobing Wu, Shiping Zhan, Shengbin Cheng, Biao Dong, Xiaofeng Wu, Yunxin Liu
Summary: Coating upconversion nanocrystals with an inert shell has been proven to effectively enhance upconversion luminescence. This study focuses on the effect of surface atomic structures on the upconversion luminescence of active cores. By improving the surface crystallinity of the inert shell, the researchers found a significant enhancement in upconversion luminescence. The improved surface crystallinity did not affect electronic transitions, but reduced scattering and absorption of excitation and emission photons.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
Ziwen Zhou, Danyang Ning, Yin Zhu, Li Xu, Yanting Yang, Enming Zhao, Lu Liu, Shuangqiang Liu
Summary: In this study, it was found that inert passivation can enhance the upconversion intensity of heavily doped nanocrystals and influence the upconversion color in two opposite directions. The mechanisms of the effects of inert shell passivation were discussed based on spectroscopic observations. The research provides guidelines for designing upconversion nanomaterials with bright emission and desired color for applications in imaging, display devices, and phototherapy.
Article
Materials Science, Ceramics
Jianxin Jiao, Yuwei Liu, Hong Wang, Xiumei Yin, Mingming Xing, Xixian Luo, Ying Tian
Summary: The study explores the upconversion luminescence and thermal sensing properties of Er3+, Yb(3+)co-doped oxysulfide, demonstrating that constructing an active shell with an optimum concentration of sensitizers is an efficient way to enhance luminescent intensities and thermal sensitivity. Increasing the Yb(3+)concentration in the shell activates new quenching pathways of Er3+ -> Yb3+ -> quencher from the core to the shell, impacting luminescent intensity. Overall, this research provides a feasible and versatile method to improve the luminescence and thermal sensing properties of Ln(3+)-based materials.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Chemistry, Analytical
Shivanand H. Nannuri, Simranjit Singh, Superb K. Misra, C. Santhosh, Sajan D. George
Summary: Anisotropic rare earth ion (RE3+) doped fluoride upconversion particles have great potential in various fields, and a facile strategy to synthesize the particles was developed in this study. By controlling the synthesis time, NaYF4: Yb, Gd, Er, and NaYF4: Yb, Gd, Tm upconversion nanorods were successfully synthesized via microwave synthesis route, and their optical properties were compared with those prepared via solvothermal technique. The phase and morphology of the particles were found to change with the increase in synthesis time. Surface modification of the particles transformed their hydrophobicity to hydrophilicity, and the surface modification route influenced the upconversion luminescence and solvent-dependent emission properties. Furthermore, the laser power dependent studies revealed that the upconversion process is a multi-photon process.
METHODS AND APPLICATIONS IN FLUORESCENCE
(2022)
Article
Nanoscience & Nanotechnology
Jian Zhang, Cong Cao, Jinsong Wang, Shiwen Li, Yu Xie
Summary: This study reports a strategy to expand the color-adjustable emission range by regulating the doping concentration of Yb3+ in core@shell upconversion nanoparticles. The multicolor UCNPs were combined with acrylamide hydrogel to construct a 3D information code with adjustable emission color. Multiple strategies were adopted to improve security and enable encryption and decryption through simple light irradiation, with the ability to edit the content.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Physical
Maohui Yuan, Kai Han, Linxuan Wang, Xu Yang, Zining Yang, Hongyan Wang, Xiaojun Xu
Summary: The introduction of appropriate Cu2+ ions into LiYF4:Yb/Er microcrystals enables the generation of highly thermally stable upconversion luminescence (UCL) for temperature sensing applications. The doping of Cu2+ ions efficiently adjusts and enhances UCL, extending the thermal quenching temperature range. These highly thermally stable microcrystals can detect temperature over a wide range and exhibit excellent thermometer performance.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
Frederike Carl, Leonie Birk, Bettina Grauel, Monica Pons, Christian Wuerth, Ute Resch-Genger, Markus Haase
Summary: A procedure to prepare luminescent LiYF4:Yb/LiYF(4)and LiYF4:Yb,Er/LiYF(4)core/shell nanocrystals was developed, showing high luminescence efficiency and low defects. Excitation power density and doping concentrations can affect the luminescent performance of these nanocrystals.
