Provided herein are phosphors of the general molecular formula:

(A.sub.2-2xEu.sub.x(Mg.sub.1-yCa.sub.y)PO.sub.4F

wherein the variables are as defined herein. Methods of producing the phosphors are also provided. In some aspects, the present disclosure provides light-emitting devices comprising these phosphors.

Provided herein are phosphors of the general molecular formula:

(A.sub.2-2xEu.sub.x(Mg.sub.1-yCa.sub.y)PO.sub.4F

wherein the variables are as defined herein. Methods of producing the phosphors are also provided. In some aspects, the present disclosure provides light-emitting devices comprising these phosphors.

Provided is a phosphor which emits near-infrared light upon irradiation of visible light or ultraviolet light. A phosphor in an embodiment of the present invention includes an inorganic substance which contains at least an Eu element, an M[3] element (M[3] is at least one selected from the group consisting of Al, Y, La and Gd.), a Si element and nitrogen element, and also contains, if necessary, at least one element selected from the group consisting of M[1] element (M[1] is Li element.), an M[2] element (M[2] is at least one element selected from the group consisting of Mg, Ca, Ba and Sr.) and an oxygen element, while the phosphor has a maximum value of an emission peak at a wavelength in the range of 760 nm or more and 850 nm and less upon irradiation by an excitation source.

Provided is a phosphor which emits near-infrared light upon irradiation of visible light or ultraviolet light. A phosphor in an embodiment of the present invention includes an inorganic substance which contains at least an Eu element, an M[3] element (M[3] is at least one selected from the group consisting of Al, Y, La and Gd.), a Si element and nitrogen element, and also contains, if necessary, at least one element selected from the group consisting of M[1] element (M[1] is Li element.), an M[2] element (M[2] is at least one element selected from the group consisting of Mg, Ca, Ba and Sr.) and an oxygen element, while the phosphor has a maximum value of an emission peak at a wavelength in the range of 760 nm or more and 850 nm and less upon irradiation by an excitation source.

A method for preparing carbon-functionalized praseodymium oxide includes the following steps: dissolving Pr(NO.sub.3).sub.3.6H.sub.2O in an acid dye solution and stirring to form a mixed solution; adding NH.sub.3H.sub.2O dropwise in the mixed solution while stirring to adjust a pH value of the mixed solution, thereby forming a suspension, and then aging the suspension for 2 to 4 hours; filtering, washing with water, washing with alcohol, and drying the aged suspension to obtain a carbon-functionalized Pr.sub.6O.sub.11 precursor; and placing the carbon-functional zed Pr.sub.6O.sub.11 precursor in a tube furnace under a protection of nitrogen, heating the carbon-functionalized Pr.sub.6O.sub.11 precursor to a sintering temperature at a heating rate of 4 to 6 degrees Celsius/min, keeping at the sintering temperature for 3 to 4 hours, and then cooling to room temperature, thereby obtaining the carbon-functionalized. Pr.sub.6O.sub.11.

A method for preparing carbon-functionalized praseodymium oxide includes the following steps: dissolving Pr(NO.sub.3).sub.3.6H.sub.2O in an acid dye solution and stirring to form a mixed solution; adding NH.sub.3H.sub.2O dropwise in the mixed solution while stirring to adjust a pH value of the mixed solution, thereby forming a suspension, and then aging the suspension for 2 to 4 hours; filtering, washing with water, washing with alcohol, and drying the aged suspension to obtain a carbon-functionalized Pr.sub.6O.sub.11 precursor; and placing the carbon-functional zed Pr.sub.6O.sub.11 precursor in a tube furnace under a protection of nitrogen, heating the carbon-functionalized Pr.sub.6O.sub.11 precursor to a sintering temperature at a heating rate of 4 to 6 degrees Celsius/min, keeping at the sintering temperature for 3 to 4 hours, and then cooling to room temperature, thereby obtaining the carbon-functionalized. Pr.sub.6O.sub.11.

Doped cerium oxide particles may comprise about 90 weight percent (wt. %) to about 99.9 wt. % cerium oxide (CeO.sub.2) and up to about 10 wt. % dopant. Exemplary doped cerium oxide particles may have a BET specific surface area of more than 150 m.sup.2/g after calcination at 500° C. for 8 hours. Exemplary doped cerium oxide particles may have an oxygen storage capacity (OSC) of more than 900 μmol.Math.O.sub.2/g after calcination at 500° C. for 8 hours.

Doped cerium oxide particles may comprise about 90 weight percent (wt. %) to about 99.9 wt. % cerium oxide (CeO.sub.2) and up to about 10 wt. % dopant. Exemplary doped cerium oxide particles may have a BET specific surface area of more than 150 m.sup.2/g after calcination at 500° C. for 8 hours. Exemplary doped cerium oxide particles may have an oxygen storage capacity (OSC) of more than 900 μmol.Math.O.sub.2/g after calcination at 500° C. for 8 hours.

Disclosed herein are embodiments of composite hexagonal ferrite materials formed from a combination of Y phase and Z phase hexagonal ferrite materials. Advantageously, embodiments of the material can have a high resonant frequency as well as a high permeability. In some embodiments, the materials can be useful for magnetodielectric antennas.

Disclosed herein are embodiments of composite hexagonal ferrite materials formed from a combination of Y phase and Z phase hexagonal ferrite materials. Advantageously, embodiments of the material can have a high resonant frequency as well as a high permeability. In some embodiments, the materials can be useful for magnetodielectric antennas.