title: Fast Responsive and Controllable Liquid Transport on a Magnetic Fluid/Nanoarray Composite Interface.
abstract: Controllable liquid transport on surface is expected to occur by manipulating the gradient of surface tension/Laplace pressure and external stimuli, which has been intensively studied on solid or liquid interface. However, it still faces challenges of slow response rate, and uncontrollable transport speed and direction. Here, we demonstrate fast responsive and controllable liquid transport on a smart magnetic fluid/nanoarray interface, i.e., a composite interface, via modulation of an external magnetic field. The wettability of the composite interface to water instantaneously responds to gradient magnetic field due to the magnetically driven composite interface gradient roughness transition that takes place within a millisecond, which is at least 1 order of magnitude faster than that of other responsive surfaces. A water droplet can follow the motion of the gradient composite interface structure as it responds to the gradient magnetic field motion. Moreover, the water droplet transport direction can be controlled by modulating the motion direction of the gradient magnetic field. The composite interface can be used as a pump for the transport of immiscible liquids and other objects in the microchannel, which suggests a way to design smart interface materials and microfluidic devices.
authors.affiliation: Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, Beijing Key Laboratory of Bio-Inspired Energy Materials and Devices, School of Chemistry and Environment, Beihang University , Beijing 100191, P. R. China.|Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong , Innovation Campus, North Wollongong, New South Wales 2500, Australia.|UOW-BUAA Joint Research Centre, University of Wollongong , North Wollongong, New South Wales 2500, Australia.
authors.forename: Dongliang
authors.initials: D
authors.lastname: Tian
authors.affiliation: Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, Beijing Key Laboratory of Bio-Inspired Energy Materials and Devices, School of Chemistry and Environment, Beihang University , Beijing 100191, P. R. China.
authors.forename: Na
authors.initials: N
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, Beijing Key Laboratory of Bio-Inspired Energy Materials and Devices, School of Chemistry and Environment, Beihang University , Beijing 100191, P. R. China.
authors.forename: Xi
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, Beijing Key Laboratory of Bio-Inspired Energy Materials and Devices, School of Chemistry and Environment, Beihang University , Beijing 100191, P. R. China.
authors.forename: Guanglei
authors.initials: G
authors.lastname: Hou
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong , Innovation Campus, North Wollongong, New South Wales 2500, Australia.|UOW-BUAA Joint Research Centre, University of Wollongong , North Wollongong, New South Wales 2500, Australia.
authors.forename: Yi
authors.initials: Y
authors.lastname: Du
authors.affiliation: Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, Beijing Key Laboratory of Bio-Inspired Energy Materials and Devices, School of Chemistry and Environment, Beihang University , Beijing 100191, P. R. China.|Laboratory of Bioinspired Smart Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China.|UOW-BUAA Joint Research Centre, University of Wollongong , North Wollongong, New South Wales 2500, Australia.
authors.forename: Lei
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, University of Wollongong , Innovation Campus, North Wollongong, New South Wales 2500, Australia.|UOW-BUAA Joint Research Centre, University of Wollongong , North Wollongong, New South Wales 2500, Australia.
authors.forename: Shi Xue
authors.initials: SX
authors.lastname: Dou
keywords: composite interface; fast responsive; liquid transport; magnetic fluid; nanoarray