An All-Organic Aqueous Battery Powered by Adsorbed Quinone.

The need for cost-effective, safe energy storage has led to unprecedentedly complex designs of materials and structures to meet stringent requirements. Yet, it remains a question whether we can eventually afford the manufacturing of these new materials and structures at a practical cost. Here, we introduce a new approach toward an all-organic aqueous battery through one-step, solution-phase adsorption. In this battery, two quinone molecules with different redox potentials adsorb onto two porous carbon electrodes to serve as the negative and the positive electrodes. For the negative side, cyclic voltammetry shows a high surface coverage of 66 pmol/cm2 for the adsorbed quinone (anthraquinone-2,7-disulfonate), which enables a stable capacity of 77 mAh/g. The full battery, operating in 1 M sulfuric acid, delivers more than 80% of its capacity at rates of up to 60C, and it retains more than 70% of the capacity after 600 cycles. As the battery adopts the typical build of a supercapacitor, this adsorption-based approach should apply broadly to achieve low-cost, safe storage. The work also provides a quantitative account of the electrochemistry of quinone adsorbed on carbon, which bears significance in the exploitation of quinone molecules in various electrochemical applications.