US 11,680,204 B2 · Down-shifting nanophosphors, method for preparing the same, and luminescent solar concentrator using the same

Abstract

The present disclosure relates to down-shifting nanophosphors, a method for preparing the same, and a luminescent solar concentrator (LSC) using the same. The down-shifting nanophosphors according to an embodiment of the present disclosure include a core including NaYF4 nanocrystals doped with neodymium (Nd) and ytterbium (Yb), and further include a neodymium (Nd)-doped crystalline shell surrounding the core, or further include a NaYF4 crystalline shell surrounding the crystalline shell. Therefore, the down-shifting nanophosphors efficiently absorb near infrared rays with a wavelength range of 700-900 nm and efficiently emit near infrared rays with a wavelength range of 950-1050 nm. In addition, the down-shifting nanophosphors according to an embodiment of the present disclosure has a size of 60 nm or less, and thus can be applied to manufacture transparent LSC films with ease and can realize transparent solar cell modules having high near infrared ray shifting efficiency.

Claims17

Dependent claims

Down-shifting nanophosphors comprising a core-shell-shell structure including a core of Nd3+-doped and Yb3+-doped fluoride-based nanoparticles represented by the following Chemical Formula 1:

NaY1-x-yF4:Nd3+x,Yb3+y [Chemical Formula 1]
wherein x is a real number satisfying 0.05≤x≤0.9, and y is a real number satisfying 0<y≤0.5, with the proviso that 0.05<x+y≤1,
an active shell that surrounds the core, and
an inactive shell containing NaYF4 nanocrystals, wherein the inactive shell surrounds the active shell, wherein the down-shifting nanophosphors absorb near infrared rays with a wavelength range of 700-900 nm and emit near infrared rays with a wavelength range of 950-1050 nm.

1 more element

A method for preparing down-shifting nanophosphors for a transparent luminescent solar concentrator (TLSC), comprising the steps of:

(1) mixing an yttrium (Y) compound, neodymium (Nd) compound, ytterbium (Yb) compound, oleic acid and 1-octadecene, followed by heating, to form a first mixed solution containing a lanthanoid complex;
(2) mixing the first mixed solution with a mixed solution of a sodium compound, fluorine compound and an alcohol to form a first reaction solution;
(3) removing the alcohol from the first reaction solution and carrying out heat treatment to form Nd3+- and Yb3+-doped fluoride-based nanoparticles having a structure of hexagonal system represented by the following Chemical Formula 1:
NaY1-x-yF4:Nd3+x,Yb3+y [Chemical Formula 1]
wherein x is a real number satisfying 0.05≤x≤0.9, and y is a real number satisfying 0<y≤0.5, with the proviso that 0.05<x+y≤1;
(4) mixing an yttrium compound, neodymium compound, oleic acid and 1-octadecene, followed by heating, to form a second mixed solution containing a lanthanoid complex,
(5) mixing the second mixed solution with the solution containing the nanoparticles represented by Chemical Formula 1, obtained from step (3), and with a mixed solution of a sodium compound, flourine compound and an alcohol to form a second reaction solution;
(6) removing the alcohol from the second reaction solution and carrying out heat treatment to form active shells containing a Nd3+-doped fluoride-based crystalline compound represented by the following Chemical Formula 2 on the surfaces of the cores including the nanoparticles represented by Chemical Formula 1, thereby providing nanophosphors having a core-shell structure:
NaY1-pF4:Nd3+p [Chemical Formula 2]
wherein p is a real number satisfying 0<p≤0.5;
(7) mixing an yttrium compound, oleic acid and 1-octadecene, followed by heating, to form a third mixed solution;
(8) mixing the third mixed solution with the solution containing the cores and the active shells, obtained from step (6), and with a mixed solution of a sodium compound, fluorine compound and an alcohol to form a third reaction solution;
and
(9) removing the alcohol from the third reaction solution and carrying out heat treatment to form inactive shells containing NaYF4 nanocrystals on the surfaces of the active shells, thereby providing nanophosphors having a core-shell-shell structure, wherein the nanophosphors absorb near infrared rays with a wavelength range of 700-900 nm and emit near infrared rays with a wavelength range of 950-1050 nm.

11 more elements

Dependencies are inferred from the claim text.

Down-shifting nanophosphors, method for preparing the same, and luminescent solar concentrator using the same

Life of this patent

Down-shifting nanophosphors, method for preparing the same, and luminescent solar concentrator using the same

Life of this patent

Abstract

Claims17