Synthesis of well-ordered nanospheres with uniform mesopores assisted by basic amino acids

We applied basic amino acids in place of NH3 to the well-known Stöber method for preparing silica spheres; the hydrolysis and condensation reactions of tetraethyl orthosilicate were conducted in the presence of basic amino acids such as L-lysine and L-arginine. The obtained silica spheres, which are of uniform size of 12 nm, are well-ordered, forming a cubic closed pack (ccp) structure, Fm-3m space group. The arrangement of uniform spheres simultaneously creates intraparticle uniform mesopores of about 3 nm. We also succeeded in the preparation of exact carbon replica with uniform mesopores by using the silica nanospheres as a template. The results shown here are the first example of the arrangement of silica nanospheres assisted by simple biomolecules, leading to the development of a novel family of ordered mesoporous materials, which will open up a wide range of possibilities for the synthesis of spontaneously assembled nano-structured materials.