Protonated montmorillonite as a highly effective proton-conductivity enhancer in p-PBI membranes for PEM fuel cells

A series of p-PBI phosphoric acid doped membranes, containing high levels of protonated montmorilonite (MMT-H), have been prepared using an easy and efficient procedure. The incorporation of MMT-H results in drastic increase (over 100%) of proton conductivity and mechanical properties, compared to the Celtec®-P membrane (commercial product of BASF Fuel Cell GmbH). This phenomenon could be attributed to water and phosphoric acid trapping in the MMT-H channels. •Novel p-PBI/protonated montmorilonite membranes for fuel cell applications.•Composite membranes exhibit very high proton conductivity up to 436mScm−1.•Considerable improvement of the mechanical properties.