Anti-Static, Field Emitting, Nanoparticle Coatings

NASA has requested development of anti-static coatings for use on satellites and spacecraft in order to prevent electrostatic discharge which can destroy sensitive electronic components and cause loss of spacecraft. With the 11 year peak in solar activity expected in the years 2000 and 2001, satellite charging by solar wind will soon become critical. To meet the need to prevent spacecraft charging, nano-crystallite coatings will be developed having over 1,000,000,000 field emitting particles per square cm. The field emitters will silently discharge electrostatic charge back into space. Mixed electron and ion conducting ceramic oxides, La(0.8)Sr(0.2)CoO(3-x) and La(0.8)Sr(0.2)MnO(3-x), will be ground into particles with median diameter less than 300 nm using proven techniques of ceramic and colloid science. Sharp edges and corners of the nano-particles will produce local fields in excess of 10 million V per meter which are sufficient for field electron emission. These refractory ceramic oxides will not be degraded by atomic oxygen of the space environment. Electron conducting properties of the oxides will neutralize differential charging of spacecraft. Slurries of suspended nano-particles will be developed which can simply be painted onto surfaces of materials requiring protection from electrostatic discharge.