Generally each of the three acidsilicastructural phases (lamellar, hexagonal or Pm3n cubic) was prepared as follows: first,
quaternary ammonium surfactant was mixed with water and HCl or HBr. To this solution tetraethyl-orthosilicate (TEOS) was
added at room temperature and stirred for 30 min or longer. The solid product was recovered by filtration and dried at room
temperature.