Direct transformation of bijels into bicontinuous composite electrolytes using a pre-mix containing lithium salt

Journal article

We report a general strategy for making bicontinuous conducting composite materials in a controllable fashion. Our approach begins with a bicontinuous interfacially jammed emulsion gel (bijel) fabricated from a pre-mix containing a salt, here bis(trifluoromethane)sulfonimide lithium salt (LiTFSI). The resulting structure has interpenetrating ionic conducting and non-conducting domains comprised of an ethylene carbonate (EC)-rich phase and a p-xylene (xylene)-rich phase of roughly equal volumes. This is the first time that bijel fabrication has been carried out with the underlying two-fluid phase diagram modified by a salt. Diffusing polystyrene (PS) into the xylene-rich phase enables the facile formation of a PS-filled bijel in place of a multi-step polymerization of added monomers. Drying the bijel results in the selective removal of xylene, reducing the total sample volume without compromising the morphology of the EC domain. Electrochemical impedance spectroscopy of the composite electrolytes confirms the existence of ion conducting pathways.

Authors: Cai, D; Richter, F; Thijssen, J; Bruce, P; Clegg, P

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Royal Society of Chemistry
• Journal: Materials Horizons
• Publication date: 2018-02-20
• Acceptance date: 2018-02-20
• DOI: 10.1039/C7MH01038A
• EISSN: 2051-6355
• ISSN: 2051-6347