Thermal oxidation of the decahydro-closo-decaborate anion B10H102− in a silicate matrix

We have studied the thermal oxidation of composites produced by reacting sodium water glass with the B10H 10 2− anion owing to multicenter contacts and possessing a spatially branched structure. The results demonstrate that, in air between 300 and 500°C, some of the decahydro-closo-decaborate anions present in the water glass/B10H 10 2− system oxidize, which is accompanied by a large exotherm and leads to the formation of a surface borosilicate layer preventing further oxygen diffusion into the bulk of the sample and oxidation of the B10H 10 2− anion. Samples protected by a coating produced during thermal oxidation possess thermal and deformation stability up to 600°C.