Fabrication of teardrop-shaped silica particles in polyelectrolyte diluted solution through in situ sol–gel process

A new strategy to fabricate teardrop-shaped silica particles is presented. Monodispersed teardrop-like silica particles were obtained through basic catalyzed sol–gel process of tetraethoxysilane by employed sodium polyacrylate as soft template. Increasing the salt concentration of solution, the morphology of silica particles can transform from teardrop-like to hollow structures, and finally formed solid particles. The morphologies of silica particles are characterized by TEM and SEM. Our finding can be scaled up for large-scale synthesis of unusual structures of inorganic or composite materials in a predictable manner. This study is expected to provide further understanding of the role of polyelectrolyte in the synthesis of inorganic materials towards design of unusual architectures and functional materials.