{"title":"A broadband near-infrared phosphor: Solid-state synthesis, two Cr3+ sites occupation and enhanced thermal stability","authors":"","doi":"10.1016/j.jlumin.2024.120971","DOIUrl":null,"url":null,"abstract":"<div><div>The development of highly efficient, thermally stable Cr<sup>3+</sup>-activated near-infrared (NIR) phosphors has received significant attention in recent years. However, the synthesis of these phosphors often leads to environmental and safety concerns due to the presence of toxic and corrosive HF. So, we have successfully developed an HF-free synthetic route to synthesize a series of Cs<sub>2</sub>NaGa<sub>1-y</sub>Sc<sub>y</sub>F<sub>6</sub>:Cr<sup>3+</sup> phosphors. By changing the ratio of Ga<sup>3+</sup>/Sc<sup>3+</sup>, the Cs<sub>2</sub>NaGa<sub>0.5</sub>Sc<sub>0.5</sub>F<sub>6</sub>:0.11Cr<sup>3+</sup> (CNGSF:0.11Cr<sup>3+</sup>) phosphor with the strongest luminescence intensity was obtained. Two sets of NIR emission bands due to two different Cr<sup>3+</sup> sites can be observed under blue light excitation. The phosphor exhibits a high internal quantum efficiency (IQE) of 66.7 % and good thermal stability. The luminescence intensity at 423 K maintains 88.7 % of the intensity at room temperature. A NIR light-emitting diode (LED) composed of the CNGSF:0.11Cr<sup>3+</sup> phosphor and a blue InGaN chip was used as a NIR light source, and clearly visible photographs of the physical object and veins of the human hand were obtained. These images show that the phosphor has great potential for application in NIR LEDs for night vision and vein imaging.</div></div>","PeriodicalId":16159,"journal":{"name":"Journal of Luminescence","volume":null,"pages":null},"PeriodicalIF":3.3000,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Luminescence","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022231324005350","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"OPTICS","Score":null,"Total":0}
引用次数: 0
Abstract
The development of highly efficient, thermally stable Cr3+-activated near-infrared (NIR) phosphors has received significant attention in recent years. However, the synthesis of these phosphors often leads to environmental and safety concerns due to the presence of toxic and corrosive HF. So, we have successfully developed an HF-free synthetic route to synthesize a series of Cs2NaGa1-yScyF6:Cr3+ phosphors. By changing the ratio of Ga3+/Sc3+, the Cs2NaGa0.5Sc0.5F6:0.11Cr3+ (CNGSF:0.11Cr3+) phosphor with the strongest luminescence intensity was obtained. Two sets of NIR emission bands due to two different Cr3+ sites can be observed under blue light excitation. The phosphor exhibits a high internal quantum efficiency (IQE) of 66.7 % and good thermal stability. The luminescence intensity at 423 K maintains 88.7 % of the intensity at room temperature. A NIR light-emitting diode (LED) composed of the CNGSF:0.11Cr3+ phosphor and a blue InGaN chip was used as a NIR light source, and clearly visible photographs of the physical object and veins of the human hand were obtained. These images show that the phosphor has great potential for application in NIR LEDs for night vision and vein imaging.
期刊介绍:
The purpose of the Journal of Luminescence is to provide a means of communication between scientists in different disciplines who share a common interest in the electronic excited states of molecular, ionic and covalent systems, whether crystalline, amorphous, or liquid.
We invite original papers and reviews on such subjects as: exciton and polariton dynamics, dynamics of localized excited states, energy and charge transport in ordered and disordered systems, radiative and non-radiative recombination, relaxation processes, vibronic interactions in electronic excited states, photochemistry in condensed systems, excited state resonance, double resonance, spin dynamics, selective excitation spectroscopy, hole burning, coherent processes in excited states, (e.g. coherent optical transients, photon echoes, transient gratings), multiphoton processes, optical bistability, photochromism, and new techniques for the study of excited states. This list is not intended to be exhaustive. Papers in the traditional areas of optical spectroscopy (absorption, MCD, luminescence, Raman scattering) are welcome. Papers on applications (phosphors, scintillators, electro- and cathodo-luminescence, radiography, bioimaging, solar energy, energy conversion, etc.) are also welcome if they present results of scientific, rather than only technological interest. However, papers containing purely theoretical results, not related to phenomena in the excited states, as well as papers using luminescence spectroscopy to perform routine analytical chemistry or biochemistry procedures, are outside the scope of the journal. Some exceptions will be possible at the discretion of the editors.