Prof. Xuehua Zhang from University of Alberta was invited to visit East China Normal Univeristy (ECNU) during January 8-12, 2020. Prof. Zhang gave a talk on “Surface Nanodroplets: Formation, Dissolution, and Applications” in the conference room 226 of physics building at Minhang campus of ECNU in the afternoon of Jan.9. This talk was chaired by Prof. Junfeng Fang from the Director of Engineering Research Center for Nanophotonics and Advanced Instrument.

Prof. Zhang is a Canada Research Chair (Tier 1) in Soft Matter and Interfaces at the Department of Chemical and Materials Engineering, University of Alberta. Her research topics cover micro/nanobubbles on surfaces, dilution-triggered liquid-liquid phase separation in confined spaces,chemical reactions of oil nanodroplets, evaporation and de-wetting of multicomponent drops and functional surfaces.

Droplets at solid–liquid interfaces play essential roles in a broad range of fields, such as compartmentalized chemical reactions and conversions, high-throughput analysis and sensing, and super-resolution near-field imaging. In this talk, Prof. Zhang introduced their recent work which focuses on understanding and controlling the nanodroplet formation on solid surfaces. These surface nanodroplets resemble tiny liquid lenses with a typical height of <1 μm and a volume of sub-femtoliters. Prof. Zhang group has experimentally and theoretically investigated the effects from solvent mixing on the droplet formation under controlled flow conditions. A universal droplet-based platform is developed for determination of partition coefficient in water and oil phases and for fast and sensitive nanoextraction of trace of hydrophobic compounds in aqueous solutions. They further revealed how evaporation of multicomponent drops can be employed to produce a large number of supraparticles with tunable shapes and high porosity on hydrophobic surfaces. Prof. Zhang communicated with Professors and graduate students after the talk.

   Prof. Zhang also visited Engineering Research Center for Nanophotonics and Advanced Instrument and State Key Laboratory of Precision Spectroscopy and communicated with Professors and graduate students. In the meantime, graduate student Zhenxin Li from Prof. Zhang research group and Yuning Liu from A/Prof. Xiaohong Chen groups cooperated with doing some experiments for two weeks to integrate application between micro-lens and thin film solar cells.