The textural characteristics of the silica synthesized using APS and HMDS showed a marked effect due to their addition. The specific surface area, SBET, decreased with respect to that of the unchanged silica as the HMDS amount increased, and the mesoporosity increased. The analysis of the TEM micrographs showed that the increase in the added HMDS led to maintaining the spherical shape of pure silica, increasing the formation of agglomerations and also the primary particle size. The presence of flocs in the crystalline network was glimpsed, leading to a deformation of the particles. On the other hand, a high APS amount caused a visible distortion, indicating that the modifier is not only lying on the surface of the silica, but also in its network; a fact that may be assigned to the increased interaction due to the amino group of the added compound. This effect could cause the SBET decrease in the different samples..