RESUMEN
Polymer electrolyte fuel cells hold great promise for a range of applications but require advances in durability for widespread commercial uptake. Corrosion of the carbon support is one of the main degradation pathways; hence, corrosion-resilient graphene has been widely suggested as an alternative to traditional carbon black. However, the performance of bulk graphene-based electrodes is typically lower than that of commercial carbon black due to their stacking effects. This article reports a simple, scalable and non-destructive method through which the pore structure and platinum utilisation of graphene-based membrane electrode assemblies can be significantly improved. Urea is incorporated into the catalyst ink before deposition, and is then simply removed from the catalyst layer after spraying by submerging the electrode in water. This additive hinders graphene restacking and increases porosity, resulting in a significant increase in Pt utilisation and current density. This technique does not require harsh template etching and it represents a pathway to significantly improve graphene-based electrodes by introducing hierarchical porosity using scalable liquid processes.
RESUMEN
The Joule heating characteristics of functional nanoparticle decorated nanocarbon aerogels are systemically investigated in terms of electrical-thermal responses. Studies verify that nanocarbon aerogels are exceptional supporting and electric-conducting monolithic frameworks for nanoparticles, enabling stable and accurate aerogel temperature control via direct electrical heating of the nanocarbon support, and thus have important applications in electro-catalysis, energy storage, carbon capture and sorption.