A Novel Route for the Large Scale production of ZnS nanopowders for Optical Ceramic Applications

Multispectral ZnS is a window material for long wave-infrared (LWIR) in the range (0.5-12 microns). The main drawback of ZnS is an insufficient chemical and mechanical strength which leads to optical degradation of the window''s properties. Current processes involve Chemical Vapor Deposition and Hot Isostatic Pressing (HIP) resulting in high costs, longer heating schedules, and with low yields. Texas Biochemicals Inc, recently developed a novel technology to produce spherical ZnS nanopowders in house. In Phase-I project, Texas Biochemicals Inc., will advance the manufacturing technology for large scale production. This technology is environmentally benign and cost effective, to produce large scale spherical ZnS nanopowders. This nanopowder containing suitable additives will prevent grain growth of the final sintered ZnS product and still retaining high transparency in the 0.5-12 microns region. The resultant sintered product will be highly durable, chemically stable, having twice the order of magnitude in mechanical strength when compared to windows and domes that are currently existing. These multi-mode windows and domes will serve for the next generation of sensors for missiles and surveillance systems. On a follow on Phase-II project this technology will be commercialized by a leading LWIR manufacturer who is very much interested in this technology.