Full text can be accessed at the following link http://www.sciencedirect.com/science/article/pii/S0169433213017133tWe studied the effects of various surfactants on the textural properties (BET surface area, pore size,and pore volume) of the silica aerogels prepared at an ambient pressure. A simple surface modificationof silica gel prepared at an ambient pressure through hydrolysis and polycondensation of TEOS as asilica precursor was conducted using various structure directing agents. The treatment was found toinduce a significant difference in the porosity of the silica aerogel. Highly porous silica aerogels withbimodal porous structures were prepared by modifying the surface of the silica wet-gel (alcogel) withtrimethylchlorosilane (TMCS) in order to preserve its porosity. The samples were analyzed by small-angleX-ray scattering and nitrogen adsorption. In this work, a possible new type of highly porous hydrophobicsilica aerogel with a bimodal porous structure is presented. A hydrophilic extremely porous (high surfacearea and large pore volume) silica aerogel was obtained by heating the as-synthesized hydrophobicsilica aerogel at 400◦C for 1 h. There was a significant effect of structure directing agent on the texturalproperties, such as specific surface area, pore size distribution and cumulative pore volume of the silicaaerogels.