Method for preparing efficient low voltage phosphors and products produced thereby

US6402985B1 · kind B1 · utility

Assignee

• United States of America as represented by the Secretary of the Air Force · US

Inventors

• David S. Y. Hsu · Alexandria, US
• Yongchi Tian · Princeton Junction, US

Key dates

• Filing date: Mar 17, 2000
• Grant date: Jun 11, 2002
• Expiry date: Mar 17, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09K11/08
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Doped phosphors (e.g., metal orthosilicates) are made by adding solid particulate precursor to a solution of an alkoxide precursor and a dopant precursor before hydrolysis is allowed to occur. The mixture is then allowed to hydrolyze, resulting in a sol-gel condensation reaction. The solid particulate precursor can be fumed silica, and acts as a nucleation site for the sol-gel reaction product. After the sol-gel reaction, the mixture is dried and fired to form phosphors. The phosphors are especially suitable for applications in which there is low voltage operation.