This invention pertains to surfactant-templated nanometer-scale porosity
of a silica precursor solution and forming a mesoporous material by first
forming the silica precursor solution into a preform having a high
surface area to volume ratio, then rapid drying or evaporating a solvent
from the silica precursor solution. The mesoporous material may be in any
geometric form, but is preferably in the form of a film, fiber, powder or
combinations thereof. The rapid drying or evaporation of solvent from the
solution is accomplished by layer thinning, for example spin casting,
liquid drawing, and liquid spraying respectively. Production of a film is
by layer thinning, wherein a layer of the silica precursor solution is
formed on a surface followed by removal of an amount of the silica
precursor solution and leaving a geometrically thinner layer of the
silica precursor solution from which the solvent quickly escapes via
evaporation. Layer thinning may be by any method including but not
limited to squeegeeing and/or spin casting. In powder formation by spray
drying, the same conditions of fast drying exists as in spin-casting (as
well as in fiber spinning) because of the high surface-area to volume
ratio of the product. When a powder is produced by liquid spraying, the
particles or micro-bubbles within the powder are hollow spheres with
walls composed of mesoporous silica. Mesoporous fiber formation starts
with a similar silica precursor solution but with an added pre-polymer
making a pituitous mixture that is drawn into a thin strand from which
solvent is evaporated leaving the mesoporous fiber(s).