Synthesis of CuO and Cu(3)N Nanoparticles in and on Hollow Silica Spheres

Copper oxide nanoparticles within hollow mesoporous silica spheres were prepared by binding/adsorbing Cu(2+) or [Cu(NH(3))(4)(H(2)O)(2)](2+) ions on the surface of carbon spheres, followed by formation of a mesoporous silica shell by sol–gel processing and calcination in air. The CuO nanoparticles can subsequently be converted into Cu(3)N nanoparticles by nitridation with ammonia. The effect of the different copper precursors, i.e. Cu(2+) and [Cu(NH(3))(4)(H(2)O)(2)](2+), on the nanocomposites was studied. CuO nanoparticles on the outer surface of hollow silica spheres were obtained by thermal treatment of hollow CuSiO(3) spheres in air. Nitridation of the CuSiO(3) spheres with ammonia resulted in Cu(3)N@SiO(2) composites, with aggregated Cu(3)N nanoparticles on hollow silica spheres.