Innovative Metal Complex Catholytes for Aqueous Redox Flow Batteries

Aqueous Redox Flow Batteries (RFBs) have been recognized as potential candidates for large-scale grid energy storage. Nonetheless, commercial RFBs face material limitations, primarily due to the toxicity and cost of current active materials. To address this, there's an urgent need for next-generation RFBs that harness earth-abundant active materials, characterized by high solubility, optimal redox potential, and electrochemical stability. While organic and hybrid materials have been explored as alternatives, they present their own set of challenges, particularly when functioning as catholyte materials. This research will present a strategic design of metal complex catholytes for aqueous RFBs. By altering the symmetry of these metal complexes, we've achieved notable advancements in tackling solubility and crossover issues. Furthermore, our recent scattering experiments revealed the discovery that these materials form self-assembled particles in solution, paving new avenues for the design of active materials with enhanced water solubility.