Embodiments of the present disclosure describe freestanding microporous membranes, methods of fabricating freestanding microporous membranes, freestanding porous membranes as electrode separators, electrochemical cells comprising freestanding porous membranes, and the like. In one aspect, the present invention provides an electrode separator comprising a freestanding microporous membrane including at least one of a covalent organic framework and a metal organic framework, and a threading polymer associated with the freestanding microporous membrane via one or more non-covalent interactions, wherein each of the threading polymer and freestanding microporous membrane include at least one moiety that participates in the one or more non-covalent interactions.