Preparation, characterisation and application of Pd/C nanocatalyst in passive alkaline direct ethanol fuel cells (ADEFC)

This work describes the use of Pd nanocatalyst on Vulcan XC-72 (at a very low loading, 8 wt% Pd) in passive alkaline direct ethanol fuel cell (ADEFC). The average Pd particle size obtained with TEM was 3.5 ± 0.5 nm. The XRD results of the prepared Pd nanocatalysts showed the dominant fcc structure. The catalytic activity towards ethanol electro-oxidation in various concentrations of KOH was evaluated in the half-cell tests by cyclic voltammetry and chronoamperometry. Improved performance and stability on Pd/C was observed when the [hydroxyl]/[ethanol] = 1. The Pd/C nanocatalyst performance in ADEFC under passive state showed enhanced maximum current and power densities in 5 M KOH. 5 M ethanol showed power density of 7 mW cm−2 and maximum current density of 33 mA cm−2 in 1 M KOH. While at higher KOH concentration of 5 M, 5 M ethanol showed improved power density of 17 mW cm−2 and 90 mA cm−2 current density as well as stability.