New approaches towards novel composite and multilayer membranes for intermediate temperature-polymer electrolyte fuel cells and direct methanol fuel cells

• Reviews composite membranes & pros/cons of multilayer membrane (MMs) prep techniques.
• Sulphonated GO as filler has higher performance than GO in composite membranes.
• Current MMs focussed on DMFC. MMs (with improved tolerance) critical for IT-PEFC.
• Next step for MMs development-combine composite (novel polymer-filler) & MM concept.
• Ionic liquids fillers have potential for use in IT-PEFC -slowly gaining momentum.

This review analyses the current and existing literature on novel composite and multilayer membranes for Polymer Electrolyte Fuel Cell applications, including intermediate temperature polymer electrolyte fuel cell (IT-PEFC) and direct methanol fuel cell (DMFC) systems. It provides a concise scrutiny of the vast body of literature available on organic and inorganic filler based polymer membranes and links it to the new emerging trend towards novel combinations of multilayered polymer membranes for applications in DMFC and IT-PEFC. The paper carefully explores the advantages and disadvantages of the most common preparation techniques reported for multilayered membranes such as hot-pressing, casting and dip-coating and also summarises various other fresh and unique techniques employed for multilayer membrane preparation.