title: Near Infrared Light-Powered Janus Mesoporous Silica Nanoparticle Motors.
abstract: We describe fuel-free, near-infrared (NIR)-driven Janus mesoporous silica nanoparticle motors (JMSNMs) with diameters of 50, 80, and 120 nm. The Janus structure of the JMSNMs is generated by vacuum sputtering of a 10 nm Au layer on one side of the MSNMs. Upon exposure to an NIR laser, a localized photothermal effect on the Au half-shells results in the formation of thermal gradients across the JMSNMs; thus, the generated self-thermophoresis can actively drive the nanomotors to move at an ultrafast speed, for instance, up to 950 body lengths/s for 50 nm JMSNMs under an NIR laser power of 70.3 W/cm(2). The reversible "on/off" motion of the JMSNMs and their directed movement along the light gradient can be conveniently modulated by a remote NIR laser. Moreover, dynamic light scattering measurements are performed to investigate the coexisting translational and rotational motion of the JMSNMs in the presence of both self-thermophoretic forces and strong Brownian forces. These NIR-powered nanomotors demonstrate a novel strategy for overcoming the necessity of chemical fuels and exhibit a significant improvement in the maneuverability of nanomotors while providing potential cargo transportation in a biofriendly manner.
authors.affiliation: State Key Laboratory of Robotics and System (HIT), Micro/Nanotechnology Research Centre, Harbin Institute of Technology , Harbin 150080, China.
authors.forename: Mingjun
authors.initials: M
authors.lastname: Xuan
authors.affiliation: State Key Laboratory of Robotics and System (HIT), Micro/Nanotechnology Research Centre, Harbin Institute of Technology , Harbin 150080, China.
authors.forename: Zhiguang
authors.initials: Z
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Robotics and System (HIT), Micro/Nanotechnology Research Centre, Harbin Institute of Technology , Harbin 150080, China.
authors.forename: Jingxin
authors.initials: J
authors.lastname: Shao
authors.affiliation: CAS Key Lab for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology , Beijing 100190, China.
authors.forename: Luru
authors.initials: L
authors.lastname: Dai
authors.affiliation: State Key Laboratory of Robotics and System (HIT), Micro/Nanotechnology Research Centre, Harbin Institute of Technology , Harbin 150080, China.
authors.forename: Tieyan
authors.initials: T
authors.lastname: Si
authors.affiliation: State Key Laboratory of Robotics and System (HIT), Micro/Nanotechnology Research Centre, Harbin Institute of Technology , Harbin 150080, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: He