High-speed graphene@Ag-MnO₂ micromotors at low peroxide levels

Abstract

Platinum (Pt) free micro/nanomotors (MNMs) using a low content of fuels are highly desired for many applications. Herein, we demonstrate that cathodic electrofabrication can produce modified MnO₂ based microtubes and microrods as highly efficient MNMs in hydrogen peroxide (H₂O₂) as low as 0.2%. The speed of graphene/Ag-MnO₂ micromotors could be smartly regulated using a surfactant and the maximum speed of an individual micromotor exceeds 1.3 mm s⁻¹ in 0.5% H₂O₂. The propelling force and output power of the micromotors are 3.4 and 10 times as high as those of the best Pt-based micromotors reported. These Ag-MnO₂ based micromotors are envisioned to be a great promise for practical applications from biomedical delivery to environmental decontamination.