Nano-YAG:Ce phosphor compositions and their methods of preparation

1. A cerium-doped, garnet-based phosphor having the formula:

(Y,A) 3 (Al,B) 5 (O,C) 12 :Ce 3+ ; where

A is selected from the group consisting of Tb, Gd, Sm, La, Sr, Ba, Ca, and Mg, and where A substitutes for Y from in amounts ranging from about 0.1 to 100 percent;

B is selected from the group consisting of Si, Ge, B, P, and Ga, and where B substitutes for Al in amounts ranging from about 0.1 to 100 percent; and

C is selected from the group consisting of F, Cl, N, and S, and where C substitutes for O in amounts ranging from about 0.1 to 100 percent,

wherein the garnet-based phosphor contains at least some Mg substituting for Y, at least some Si substituting for Al, and at least some F or Cl substituting for O.

2. The cerium-doped, garnet-based phosphor of claim 1 , wherein the phosphor is configured to emit light ranging from about 540 to 560 when excited by radiation having a peak wavelength ranging from about 445 nm to about 460 nm, and wherein the elements in the phosphor comprise yttrium, magnesium, aluminum, silicon, oxygen and fluorine.

3. The cerium-doped, garnet-based phosphor of claim 1 , wherein the phosphor is configured to emit light ranging from about 540 to 560 when excited by radiation having a peak wavelength ranging from about 445 nm to about 460 nm, and wherein the particle size distribution ranges from about 10 nm to about 1 μm.

4. The cerium-doped, garnet-based phosphor of claim 1 , wherein the phosphor is configured to emit light ranging from about 540 to 560 when excited by radiation having a peak wavelength ranging from about 445 nm to about 460 nm, and wherein the D50 average particle size ranges from about 200 nm to about 700 nm.

5. The cerium-doped, garnet-based phosphor of claim 1 , wherein the phosphor is configured to emit light ranging from about 540 to 560 when excited by radiation having a peak wavelength ranging from about 445 nm to about 460 nm, and wherein the phosphor is represented by the formula (Y,A) 3 (Al 1-x Si x ) 5 (O 1-y C y ) 12 :Ce 3+ ; x ranges from about 0.001 to about 0.2; y ranges from about 0.001 to about 0.2; and the particle size distribution ranges from about 10 nm to about 1 μm.

6. A method of preparing a cerium-doped, garnet-based phosphor having the formula:

(Y,A) 3 (Al,B) 5 (O,C) 12 :Ce 3+ ; where

A is selected from the group consisting of Mg, Tb, Gd, Sm, La, Sr, Ba, Ca, and where

A substitutes for Y from in amounts ranging from about 0.1 to 100 percent;

B is selected from the group consisting of Si, Ge, B, P, and Ga, and where B substitutes for Al in amounts ranging from about 0.1 to 100 percent; and

C is selected from the group consisting of F, Cl, N, and S, and where C substitutes for O in amounts ranging from about 0.1 to 100 percent; the method comprising:

1) dissolving in de-ionized water desired amounts of Ce(NO 3 ) 3 .6H 2 O, Y(NO 3 ) 3 .6H 2 O, Al(NO 3 ) 3 .9H 2 O and a compound selected from the group consisting of NH 4 X, AlX 3 , and YX 3 , and dissolving desired amounts of compounds of A, B, and C in de-ionized water, where X is selected from the group consisting of F and Cl;

2) adding the solution from step 1) to an ammonia solution in a dropwise manner;

3) aging the solution of step 2), and then filtering and washing the resultant precipitant with distilled water;

4) drying the precipitate of step 3); and

5) sintering the dried product of step 4) at about 1100° C. to 1500° C. in a reducing atmosphere,

wherein the method includes substituting at least some Mg for Y, substituting at least some Si for Al, and substituting at least some F or Cl for O.

7. The method of claim 6 , further including a step of adding (CH 3 O) 4 Si to the solution resulting from step 1).

8. The method of claim 6 , wherein the A containing starting materials are selected from the group consisting of nitrates, oxides, hydroxides, carbonates, and sulfates.