2D to 3D transition of nanoparticles assembled at the liquid interface

ORAL

Abstract

With in situ atomic force microscopy (AFM) imaging, the structure of nanoparticles assembled at the water-oil interface is clearly resolved with the nanometer in 3D. The increase in the surfactant concentration in the oil phase leads to the increase in the contact angle of the nanoparticles at the water-oil interface. Unlike the prediction by equilibrium theory, a 2D monolayer to a 3D multilayer transition of nanoparticles is observed at high surfactant concentrations, which is attributed to the co-existence of completed wetted and partially wetted nanoparticles at the water-oil interface. The contact angle change and structural transition of nanoparticles induced by the increase of surfactant concentration is further confirmed macroscopically by the phase-inversion of Pickering emulsions and anomalous compliance of liquid interface. Our study sheds light on the importance of both thermodynamics and kinetics on the assembly of nanomaterials at the liquid interface and also demonstrate the advantage of using in situ AFM to characterize the assembly of nanomaterials at the liquid interface.

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Presenters

  • Yu Chai

    • Lawrence Berkeley National Laboratory

Authors

  • Yu Chai

    • Lawrence Berkeley National Laboratory

  • Alysia Lukito

    • Lawrence Berkeley National Laboratory

  • Jaffar Hasnain

    • University of California, Berkeley

  • Anju Toor

    • University of California, Berkeley

  • wenqian feng

    • Lawrence Berkeley National Laboratory

  • Yufeng Jiang

    • University of California, Berkeley
    • Lawrence Berkeley National Laboratory

  • Joe Forth

    • Lawrence Berkeley National Laboratory

  • yunhui tang

    • Lawrence Berkeley National Laboratory

  • honghao hou

    • Lawrence Berkeley National Laboratory

  • teresa williams

    • Lawrence Berkeley National Laboratory

  • ravi chandra

    • Lawrence Berkeley National Laboratory

  • dong li

    • Lawrence Berkeley National Laboratory

  • Phillip Geissler

    • University of California, Berkeley

  • brett helms

    • Lawrence Berkeley National Laboratory
    • The Molecular Foundry, Lawrence Berkeley National Laboratory

  • Thomas Russell

    • Univ of Mass - Amherst
    • Polymer Science and Engineering, University of Massachusetts Amherst
    • Lawrence Berkeley National Laboratory
    • Polymer Science and Engineering Department, UMass

  • paul ashby

    • Molecular Foundry, Lawrence Berkeley National Laboratory
    • Lawrence Berkeley National Laboratory