Nano-catalysts for Hydrogen-Bromine Redox-Flow batteries

Hydrogen-bromine redox-flow batteries (RFBs) technology offers the most economic storage solution and is considered most promising for a sustainable electricity storage solution due to its fast kinetics, highly reversible reactions and low chemical costs. The main bottleneck of conventional electrodes is the rapid fading of the hydrogen catalyst performance in the highly corrosive environment.

The crossover of Br species requires the use of a catalyst with a high PGM (platinum group metals). To increase the effectiveness of the storage system, the catalyst cost needs to be decreased (by reducing the PGM loading) whilst increasing its tolerance versus bromide species. To solve this dilemma, we investigate the combination between PGM and non-PGM metals at the nanoscale with a polymeric surface coating. We show that a 2 nm thin coating on the catalyst can effectively protects the metallic surface from corrosion in concentrated HBr and maintains a high catalytic activity.