Synthesis of mesoporous silica fibers and discoids endowed with circular pore architecture using disodium trioxosilicate as silica source

We describe the synthesis of mesoporous silica fibers and discoids using disodium trioxosilicate (Na2SiO3 · 9H2O), a convenient silica source with cetyltrimethylmmonium chloride (CTAC) as a structure directing agent under acidic condition. The molar composition of the synthesis sol is 1Na2SiO3 · 9H2O:1.5CTAC:28HCl:729H2O. The fibers and discoids, both p6mm, hexagonal, are obtained at room temperature and 70 °C, respectively. The particles are mesoporous single-crystal like with hexagonally organized pores and possess a circular architecture with pore channels running around the fiber or discoid axis endowing self-sealed-type structure to the particles. For fibers and discoids, the BET surface areas are 1330 m2/g and 1250 m2/g, mesopore diameters are 2.4 nm and 2.5 nm, and pore volumes are 0.93 cm3 and 0.96 cm3/g, respectively.