Enhancement of SO2 high temperature depolarized electrolysis by means of graphene oxide composite polybenzimidazole membranes

In the present work, Polybenzimidazole-composite membranes with graphene oxide as organic filler with different contents (0.5, 1.0, 2.0 and 3.0 wt%) were prepared and tested in a sulfur depolarized electrolyzer. The composite Graphene Oxide/Polybenzimidazole membranes show greater electrolyzer performance than a standard membrane. For the first time, actual hydrogen production is reported at high temperature in the range of 110 degrees C-140 degrees C for the sulfur dioxide depolarized electrolysis. In general, composite Graphene Oxide/Polybenzimidazole membranes showed superior performance, obtaining the highest hydrogen generation with the composite membrane with a content of 2 wt%. Furthermore, sulfur dioxide crossover is reported to decrease by increasing the amount of graphene oxide into the membrane, demonstrating the benefit of adding Graphene Oxide to a Polybenzimidazole matrix for the sulfur dioxide depolarized electrolysis.

Automated summary

This study prepared composite graphene oxide/polybenzimidazole membranes in a sulfur depolarized electrolyzer and found that they showed better performance compared to standard membranes, allowing for hydrogen production under high temperature conditions. Increasing the graphene oxide content can reduce the crossover of sulfur dioxide.