Controlled one-sided growth of Janus TiO2/MnO2 nanomotors

Designing and building new micro/nanomotors are among the most exciting challenges facing nanotechnology. Considering the expensive equipment and the high cost associated with noble metals, a scalable and reliable fabrication method is desired for the fabrication of Janus particles. In this work, we report on the preparation and characterization of self-propelled micromotors based on Janus TiO2/MnO2 nanoparticles. The Janus micromotor is constructed by growing propulsion material MnO2 nanoflakes in situ on one hemisphere of TiO2 by photoreduction of KMnO4 under aerobic conditions. The MnO2 nanoflakes can catalytically decompose hydrogen peroxide fuel to generate oxygen bubbles, which consequently repel the micromotors forward in the solution. Thus, the Janus TiO2/MnO2 nanoparticle represents a promising material for the preparation of micromotors for various biomedical or environmental applications.