PORE-SIZE AND PORE-SIZE DISTRIBUTION CONTROL OF POROUS SILICA

Porous silica is a unique matrix material for chemical sensors. In thi s paper, porous silica is prepared via the sol-gel technique. The poro sity, pore size, pore shape and pore-size distribution can be controll ed by catalysts and preparation conditions. A porosity as high as 60-7 0% can be reached. The pore size can be controlled in the range 2-100 nm. A single narrow peak and double separate peak distributions can be achieved by controlling the pH values. The pore shape can be controll ed from narrow-necked and large-abdomened shapes to fine cylindrical p ores. Applications of porous silica for chemical sensors are also disc ussed in this paper.