The Pt-Au-OSi@CS nanoparticles were prepared using positively
charged OSi@CS nanospheres as templates for adsorbing negatively
charged 1–3 nm Au nanoparticles that act as seeds in subsequent
step as nucleation sites for the reduction of platinum. Briefly, the
OSi@CS nanoparticles were dispersed in sufficient gold colloid solution
contains 1–3 nm Au nanoparticles with stirring for 8 h. Then