Montmorillonite–Polybenzimidazole Inorganic-Organic Composite Membrane with Electric Field-Aligned Proton Transport Channel for High Temperature Proton Exchange Membranes

ABSTRACT

The conductivity of high temperature proton exchange membranes (HTPEM) was improved by adding Montmorillonite (MMT) with proton counter-ions H+to polybenzimidazole containing ether units (PBI-O) based membrane. During casting procedure an external AC electric field was applied to the MMT-PBI-O-based composite membranes casting solution. The introduction of MMT nanoplatelets in HTPEM significantly improved the acid doping level and conductivity, without modifying the electrochemical/chemical stability,, dimensional stability and mechanical properties of composite membranes. The conductivity of 5%-MMT-PBI-O composite membranes was improved nearly 400% compared to pure PBI-O membranes, proving that the present technique is a potential method for fabricating HTPEM with oriented MMT nanoplatelets and taking full advantage of the bulk conductivity of the MMT nanoplatelets.

GRAPHICAL ABSTRACT

KEYWORDS:

• AC electric field
• ball milling
• composite membrane
• montmorillonite nanocomposite
• polybenzimidazole

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [Grant Number 21376022 and 21476020] and This work was supported by the the International S&T Cooperation Program of China [Grant Number 2013DFA51860].