Nano/micro-structural engineering of Nafion membranes for advanced electrochemical applications

Nafion membranes are actively electrochemical devices such as fuel cells, conventional two compartments electrochemical cells, and photoassisted electrolyzer cells. It provides good selectivity of penetrating ions from one electrode compartment to another and accelerates the separation of the products. Though the conventional Nafion membrane has been widely applied, there are still some crucial challenges, such as the flow of ions transferred by fouling, charge gradient resistance, and mechanical instabilities in long-term applications. In particular, the charge transfer resistance of the membrane is a key characteristic to realize the efficient transfer of charges across the electrodes within the electrolyte. The researchers have tried cost-effective nano/micro-structural engineering strategies to produce high-quality Nafion membranes for improved electrochemical applications. The proper surface patterning and selective functionalization or hybrid formation of Nafion with specialized materials could improve the overall mechanical strength, charge sustaining and flow rate potentials of the parent Nafion. This manuscript provides a brief overview of Nafion based nano and microstructured membrane and their modification strategies for energy conversion devices. Two strategies are shortly overviewed with respective examples: (1) physical modification via nano/micropatterning and (2) nanocomposite formation with selective materials. The modified Nafion membranes by various structural engineering strategies propose new and effective pathways to enhance the performance of energy conversion devices, which are keys for solving current environmental issues.