Self-propelled micromotors based on Au–mesoporous silica nanorods

Abstract

Here, a chemical powered micromotor from the assembly of Au–SiO₂ nanorods is presented. This new micromotor can be propelled efficiently by hydrogen bubbles generated from a hydrolysis reaction of aqueous NaBH₄ and KBH₄ and by oxygen bubbles produced by decomposition of H₂O₂. The monodisperse Au nanoparticles in mesoporous silica particles could catalyze the decomposition of two different kinds of fuels and produce bubbles. High speeds of 80 μm s⁻¹ and recycles of more than 30 times are achieved in both NaBH₄ and H₂O₂ media. Locomotion and rolling forms of movement were found. The locomotion forms can be obtained in a larger proportion by patterning the Au–SiO₂ nanorods and a PDMS membrane. These micromotors that use multiple fuel sources to power them offer a broader scope of preparation and show considerable promise for diverse applications of nanomotors in different chemical environments.