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A series of cross-linked piperidinium-based anion-exchange membranes (AEMs) with an aliphatic main chain was prepared by UV-initiated polymerization of 1-methyl-1-(4-vinylbenzyl)­piperidinium chloride ([MVBPip]­[Cl]). The chemical structures of [MVBPip]­[Cl] and piperidinium-based membranes were studied by nuclear magnetic resonance (NMR) and IR spectroscopy, respectively. The piperidinium cation showed excellent alkaline stability, demonstrated by 1H NMR spectroscopy. The water uptake and conductivity of the piperidinium-based AEMs were enhanced by an increase in [MVBPip]­[Cl] content. A hydrophilic/hydrophobic microphase-separated structure was clearly detectable in the piperidinium-based AEMs. The transparent and mechanically robust piperidinium-based AEMs exhibited excellent chemical stability in 2 M KOH solution with the conductivity reaching 57.4 mS cm–1 (80 °C). The maximum power density of the single cell fabricated with piperidinium-based AEMs achieved 108.8 mW cm–2. These results indicate that the cross-linked piperidinium-based AEMs with an aliphatic main chain are promising materials for application in fuel cells.

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Catalysts are a key component of polymer electrolyte membrane fuel cells (PEMFCs). In this work, nitrogen-doped three-dimensional graphene-supported platinum (Pt-3DNG) catalysts are successfully prepared and characterized. SEM and TEM images show the Pt nanoparticles are uniformly dispersed in the sheets of nitrogen-doped 3DNG. Compared with that of the commercial Pt/C catalysts, Pt-3DNG show much better oxygen reduction reaction (ORR) activity and cycling stability, and the reduction in limit current density after 1000 cycles is only about 1.6% for the Pt-3DNG catalysts, whereas 7.2% for the commercial Pt/C catalysts. The single cell using Pt-3DNG catalysts in both the anode and the cathode show a higher peak power density (21.47[Formula: see text]mW cm[Formula: see text] than that using commercial Pt/C catalysts (20.17[Formula: see text]mW cm[Formula: see text] under the same conditions. These properties make this type of catalyst suitable for the application in PEMFCs.