Analysis of mass-transport losses in structure-modified electrodes of air–hydrogen fuel cells by the current–voltage characteristic method

We have tested platinum–carbon electrodes with mixed conductivity as parts of membrane electrode assemblies of fuel cells containing structure-modifying additives with different structural elements (carbon nanotubes with extended structural elements and graphene-like materials with nearly 2D planes). Mass-transport losses of molecular oxygen transfer in these electrodes have been investigated on the basis of data on the limiting current density obtained in the potentiodynamic and potentiostatic regimes. The pressure dependences of the current density have been plotted using various conditions of measurements. Limiting factors and oxygen transport mechanisms in the tested structures and the role of introduced modifiers have been determined.