Cerium-doped alkaline-earth hafnium oxide scintillators having improved transparency and method of making the same

A method for producing a cerium-doped alkaline earth hafnium oxide scintillator composition that comprises at least one alkaline earth metal selected from the group consisting of barium, strontium, calcium, and combinations thereof;

• said method comprising the steps of:
• providing a mixture of compounds of cerium, hafnium, and said at least one alkaline earth metal;
• firing said mixture in an oxygen-containing atmosphere at a firing temperature for a time sufficient to convert said mixture to a cerium-doped alkaline earth hafnium oxide;
• and
• annealing said cerium-doped alkaline earth hafnium oxide to produce said cerium-doped alkaline earth hafnium oxide scintillator composition;
• wherein amounts of compounds are chosen to obtain the final desired composition of said scintillator, and said scintillator is capable of emitting visible light in response to an excitation of high-energy radiation selected from the group consisting of X, β, and γ radiation.

A method for producing a shaped cerium-doped alkaline earth hafnium oxide scintillator that comprises at least one alkaline earth metal selected from the group consisting of barium, strontium, calcium, and combinations thereof, said method comprising the steps of:

• providing a starting mixture of compounds of cerium, hafnium, and said at least one alkaline earth metal;
• converting said compounds in said starting mixture substantially to water-insoluble oxygen-containing compounds to form a mixture of water-insoluble oxygen-containing compounds;
• firing said mixture of said oxygen-containing compounds at a firing temperature for a time sufficient to convert said mixture to a cerium-doped alkaline earth hafnium oxide;
• and
• hot isostatically pressing said cerium-doped alkaline earth hafnium oxide to form said shaped cerium-doped alkaline earth hafnium oxide scintillator;
• wherein amounts of said compounds are chosen to obtain a final desired composition of said scintillator, and said scintillator is capable of emitting visible light in response to an excitation of high-energy radiation selected from the group consisting of X, β, and γ radiation.

A method for producing a cerium-doped alkaline earth hafnium oxide scintillator composition that comprises at least one alkaline earth metal selected from the group consisting of barium, strontium, calcium, and combinations thereof;

• said method comprising the steps of:
• providing a first solution comprising compounds of at least cerium, hafnium, and said at least one alkaline earth metal;
• providing a second solution selected from the group consisting of ammonium hydroxide;
• alkyl esters of a di-carboxylic acid selected from the group consisting of oxalic acid, malonic acid, succinic acid, and glutaric acid;
• amines selected from the group consisting of methanolamine, ethanolamine, propanolamine, dimethanolamine, diethanolamine, dipropanolamine, trimethanolamine, triethanolamine, and tripropanolamine;
• and mixtures thereof;
• mixing together said first solution and said second solution to form a precipitate mixture of oxygen-containing compounds of at least cerium, hafnium, and said at least one alkaline earth metal;
• separating said precipitate mixture from a supernatant liquid;
• firing said precipitate mixture at a temperature and for a time sufficient to convert said dried precipitate mixture to said cerium-doped hafnium oxide scintillator composition;
• wherein amounts of said compounds are chosen to obtain a final desired composition of said scintillator that is capable of emitting visible light in response to an excitation of high-energy radiation selected from the group consisting of X, β, and γ radiation.

A method for producing a shaped cerium-doped alkaline earth hafnium oxide scintillator that comprises at least one alkaline earth metal selected from the group consisting of barium, strontium, calcium, and combinations thereof, said method comprising the steps of:

• providing a first solution that comprises amounts of compounds of at least cerium, hafnium, and said at least one alkaline earth metal;
• providing a second solution selected from the group consisting of ammonium hydroxide;
• alkyl esters of a di-carboxylic acid selected from the group consisting of oxalic acid, malonic acid, succinic acid, and glutaric acid;
• amines selected from the group consisting of methanolamine, ethanolamine, propanolamine, dimethanolamine, diethanolamine, dipropanolamine, trimethanolamine, triethanolamine, and tripropanolamine;
• and mixtures thereof;
• mixing together said first solution and said second solution to form a precipitate mixture of oxygen-containing compounds of at least cerium, hafnium, and said at least one alkaline earth metal;
• separating said precipitate mixture from a supernatant liquid;
• firing said precipitate mixture at a temperature and for a time sufficient to convert said precipitate mixture to a cerium-doped hafnium oxide;
• and
• hot isostatically pressing said cerium-doped hafnium oxide to form said shaped cerium-doped alkaline earth hafnium oxide scintillator;
• wherein amounts of compounds are chosen to obtain a final desired composition of said scintillator that is capable of emitting visible light in response to an excitation of high-energy radiation selected from the group consisting of X, β, and γ radiation.