title: Highly Efficient Light-Driven TiO2-Au Janus Micromotors.
abstract: A highly efficient light-driven photocatalytic TiO2-Au Janus micromotor with wireless steering and velocity control is described. Unlike chemically propelled micromotors which commonly require the addition of surfactants or toxic chemical fuels, the fuel-free Janus micromotor (diameter ∼1.0 μm) can be powered in pure water under an extremely low ultraviolet light intensity (2.5 × 10(-3) W/cm(2)), and with 40 × 10(-3) W/cm(2), they can reach a high speed of 25 body length/s, which is comparable to common Pt-based chemically induced self-electrophoretic Janus micromotors. The photocatalytic propulsion can be switched on and off by incident light modulation. In addition, the speed of the photocatalytic TiO2-Au Janus micromotor can be accelerated by increasing the light intensity or by adding low concentrations of chemical fuel H2O2 (i.e., 0.1%). The attractive fuel-free propulsion performance, fast movement triggering response, low light energy requirement, and precise motion control of the TiO2-Au Janus photocatalytic micromotor hold considerable promise for diverse practical applications.
authors.affiliation: Research Institute of Materials Science, South China University of Technology , Guangzhou 510640, China.
authors.forename: Renfeng
authors.initials: R
authors.lastname: Dong
authors.affiliation: Research Institute of Materials Science, South China University of Technology , Guangzhou 510640, China.
authors.forename: Qilu
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Nanoengineering, University of California San Diego , La Jolla, California 92093, United States.
authors.forename: Wei
authors.initials: W
authors.lastname: Gao
authors.affiliation: Department of Nanoengineering, University of California San Diego , La Jolla, California 92093, United States.
authors.forename: Allen
authors.initials: A
authors.lastname: Pei
authors.affiliation: Research Institute of Materials Science, South China University of Technology , Guangzhou 510640, China.
authors.forename: Biye
authors.initials: B
authors.lastname: Ren
keywords: Janus micormotors; TiO2; fuel free; light driven; self-electrophoresis