Persistent phosphor

A method for producing a phosphor, the method comprising:

• providing amounts of oxygen-containing compounds of europium, RE, and at least one alkaline-earth metal selected from the group consisting of Ba, Sr, Ca, and combinations thereof, wherein RE is at least one of neodymium or dysprosium;
• mixing together the oxygen-containing compounds to form a mixture;
• and
• then firing the mixture at a temperature between about 900° C. and about 1700° C. under a reducing atmosphere for a sufficient period of time to convert the mixture to a phosphor comprising a general formula of Ax-y-zAl2-m-n-o-pO4:Euy, REz, Bm, Znn, Coo, Scp wherein:
• A may be Ba, Sr, Ca, or a combination of these metals;
• x is between about 0.75 and 1.3;
• y is between about 0.0005 and 0.1;
• z is between about 0.0005 and 0.1;
• m is between about 0.0005 and 0.30;
• n is between about 0.0005 and 0.10;
• o is between about 0 and 0.01;
• p is between about 0 and 0.05;
• and
• RE is Dy, Nd, or a combination thereof.

An article of manufacture containing a phosphor, comprising:

• a structure;
• and
• a phosphor comprising a general formula of Ax-y-zAl2-m-n-o-pO4:Euy, REz, Bm, Znn, Coo, Scp wherein:
• A may be Ba, Sr, Ca, or a combination of these metals;
• x is between about 0.75 and 1.3;
• y is between about 0.0005 and 0.1;
• z is between about 0.0005 and 0.1;
• m is between about 0.0005 and 0.30;
• n is between about 0.0005 and 0.10;
• o is between about 0 and 0.01;
• p is between about 0 and 0.05;
• and
• RE is Dy, Nd, or a combination thereof.

A method for making nano-scale particles of an oxide based phosphor, comprising:

• forming a first micro-emulsion;
• forming a second micro-emulsion;
• mixing the first and the second micro-emulsion to form a solution;
• isolating precursor particles from the solution;
• and
• forming nano-scale particles of the oxide based phosphor from the precursor particles;
• wherein the oxide based phosphor comprises a general formula of Ax-y-zAl2-m-n-o-pO4:Euy, REz, Bm, Znn, Coo, Scp wherein:
• A may be Ba, Sr, Ca, or a combination of these metals;
• x is between about 0.75 and 1.3;
• y is between about 0.0005 and 0.1;
• z is between about 0.0005 and 0.1;
• m is between about 0.0005 and 0.30;
• n is between about 0.0005 and 0.10;
• o is between about 0 and 0.01;
• p is between about 0 and 0.05;
• and
• RE is Dy, Nd, or a combination thereof.

A method for making nano-scale particles of an oxide based phosphor, comprising:

• forming an organic metal solution;
• forming a first micro-emulsion;
• heating the organic metal solution, and slowly adding the organic metal solution to the first micro-emulsion to form a second micro-emulsion;
• isolating precursor particles from the second micro-emulsion solution;
• and
• forming nano-scale particles of the oxide based phosphor from the precursor particles, wherein the oxide based phosphor comprises a general formula of Ax-y-zAl2-m-n-o-pO4:Euy, REz, Bm, Znn, Coo, Scp wherein:
• A may be Ba, Sr, Ca, or a combination of these metals;
• x is between about 0.75 and 1.3;
• y is between about 0.0005 and 0.1;
• z is between about 0.0005 and 0.1;
• m is between about 0.0005 and 0.30;
• n is between about 0.0005 and 0.10;
• o is between about 0 and 0.01;
• p is between about 0 and 0.05;
• and
• RE is Dy, Nd, or a combination thereof.