Hierarchical Lotus Leaf-Like Mesoporous Silica Material with Unique Bilayer and Hollow Sandwich-Like Folds: Synthesis, Mechanism, and Applications

A facile and straightforward strategy was developed to synthesize hierarchical lotus leaf-like mesoporous silica material (LLMSM) with unique bilayer and hollow sandwich-like folds using hexadecylamine as a structure-directing agent, high molecular weight polyvinylpyrrolidone as a structure-stabilizing agent, and tetraethyl orthosilicate as a silica precursor in the mixed solvents of water and ethanol. The formation mechanism of LLMSM was proposed based on a series of experimental investigations. This new particulate platform exhibited superior adsorption capacity toward organic dye, effective catalytic reduction of 4-nitrophenol as a Ag catalyst supporter, and a multistage sustained drug release profile. Many other applications can be also envisaged for such a hierarchical structure.