Silicate Phosphors

An Alternate Light Source for Architectural Sources
Architecture, April, 1999

In a collaborative effort that stretched from Southern California to Hong Kong, a team of university researchers - operating within a meager $9,000 budget - developed an innovative and potentially ground-breaking new lighting application for a newly discovered material: silicate phosphors. The silicate phosphors, which come in powder, granular, and liquid form, are compounds that contain silicon, oxygen, and carbon and radiate a bright white light when heated or excited with ultraviolet light. Noting that the mercury and other metal-based phosphors typically used in fluorescent lighting are expensive and toxic when disposed of, the research team sought an inexpensive, nontoxic alternative that was also more energy efficient. They found it in the silicate phosphors, which were discovered by coinvestigator Michael J. Sailor form the University of California, San Diego (UCSD).

To test their proposals, the chemists and architects from both UCSD and the Chinese University of Hong Kong, led by architect Steven Lombardi, developed a prototype - a decorative entry marker, called gateway, for the Hong Kong airport that combines light with bamboo sculpture - and experimented with different chemical ingredients to make the silicate phosphors brighter and more stable. The researchers discovered that adding aluminum to the ingredients generated the most efficient light and held the greatest promise for brightness and chemical stability. Silicate phosphors could be employed in everything from task lighting to general building lighting. The researchers are now conducting a second phase of research in which they refine their system and test its feasibility for commercial production.