Synthesis of Silica/Carbon-Encapsulated Core−Shell Spheres:  Templates for Other Unique Core−Shell Structures and Applications in in Situ Loading of Noble-Metal Nanoparticles

Silica@carbon core-shell spheres have been synthesized via a hydrothermal carbonization procedure with glucose as the carbon precursor and silica spheres as the cores. Such SiO(2)@C core-shell spheres can be further used as templates to produce SiO(2)@C@SiO(2), and SiO(2)@SiO(2) spheres with a vacant region in two SiO(2) shells, noble-metal nanoparticle loaded SiO(2)@C core-shell spheres, and hollow carbon capsules through different follow-up processes. The obtained core-shell materials possess remarkable chemical reactivity in reducing noble-metal ions to nanoparticles, e.g., platinum. These unique core-shell spherical composites could find applications in catalyst supports, adsorbents, encapsulation, nanoreactors, and reaction templates.