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A dual-excited and dual near-infrared emission phosphor Mg 14 Ge 5 O 24 :Cr 3+ ,Cr 4+ with a super broad band for biological detection.
- Source :
-
Dalton transactions (Cambridge, England : 2003) [Dalton Trans] 2021 Jan 07; Vol. 50 (1), pp. 311-322. Date of Electronic Publication: 2020 Dec 10. - Publication Year :
- 2021
-
Abstract
- Recently, near-infrared phosphors that can be applied in many fields such as night vision, agriculture, and bio-applications have attracted considerable interest in the research field worldwide. Herein, a multi-functional and dual-excited near-infrared phosphor Mg <subscript>14</subscript> Ge <subscript>5</subscript> O <subscript>24</subscript> :Cr <superscript>3+</superscript> ,Cr <superscript>4+</superscript> which provides two emission bands ranging from 700 nm to 1100 nm and 1100 nm to 1700 nm has been obtained via the traditional high-temperature solid state reaction. The presence of six and four coordination ions in the olivine structure of Mg <subscript>14</subscript> Ge <subscript>5</subscript> O <subscript>24</subscript> provides a favorable environment for the coexistence of Cr <superscript>3+</superscript> and Cr <superscript>4+</superscript> . Under blue light excitation, a super broad emission band ranging from 650 nm to 1100 nm with a full-width at half maximum (FWHM) of 266 nm is assigned to the spin-allowed <superscript>4</superscript> T <subscript>2</subscript> (4F) → <superscript>4</superscript> A <subscript>2</subscript> transition of Cr <superscript>3+</superscript> in a weak crystal-field environment. With the increase in the concentration of Cr ions, more and more Cr <superscript>4+</superscript> preferentially occupies four coordinated Ge <superscript>4+</superscript> sites, and the other broad emission band ranging from 1100 nm to 1600 nm with a FWHM of 256 nm that comes from the <superscript>3</superscript> T <subscript>2</subscript> → <superscript>3</superscript> A <subscript>2</subscript> transition of Cr <superscript>4+</superscript> is observed. The phenomenon of NIR I region excitation and NIR II region emission appears. The transmission experiment of a biological tissue proves that the Mg <subscript>14</subscript> Ge <subscript>5</subscript> O <subscript>24</subscript> :Cr <superscript>3+</superscript> ,Cr <superscript>4+</superscript> phosphor has potential applications in the field of near-infrared light-emitting diodes for biological detection.
Details
- Language :
- English
- ISSN :
- 1477-9234
- Volume :
- 50
- Issue :
- 1
- Database :
- MEDLINE
- Journal :
- Dalton transactions (Cambridge, England : 2003)
- Publication Type :
- Academic Journal
- Accession number :
- 33300918
- Full Text :
- https://doi.org/10.1039/d0dt03554h