Fabrication of Bimodal Porous Silica with Zeolite Crystal Core/Mesoporous Shell and Corresponding Nonspherical Hollow Carbon Capsules

摘要

Novel core-shell silicate particles, each of which consists of a zeolite crystal core and mesoporous shell (ZCMS) were synthesized using silicalite-1 or A structure as a zeolite crystal. The ZCMS core-shell particles are unique because they maintained zeolite specific nonspherical crystal shape, and have hierarchical porosity of both uniform microporous core and mesoporous shell coexisting in a particle framework. The nonspherical bimodal porous core-shell particles were then utilized as templates to fabricate new carbon replicas. Interestingly, the pore replication process was carried out only through the mesopores in the shell, but not through the narrow micropores in the zeolite core, resulting in nonspherical carbon nanocases with hollow core and mesoporous shell (HCMS) structure. The specific nonspherical shapes of the zeolite crystals were transferred onto their corresponding carbon nanocases.