A version of Stober synthesis enabling the facile prediction of silica nanospheres size for the fabrication of opal photonic crystals

摘要

A sol-gel synthesis procedure based on the method proposed by Stober et al. (J Colloid Interface Sci 26: 302-315, 1968) has been adopted for the one-step preparation of mono-dispersed silica nanospheres. An excellent control of the particle diameter over a wide range is obtained by varying the amount of silicon alkoxide only, while the concentration of all other components is kept fixed: this allows the fabrication of artificial opals with a finely tuned and precisely predictable lattice parameter.