Electrochemical redox behavior of organic quinone compounds in aqueous metal ion electrolytes

Organic quinone compounds are promising electrode materials for aqueous rocking-chair batteries due to chemical inert toward aqueous solutions and wide feasibility of various charge carriers. However, in aqueous electrolytes, the ion-pairing effect of different charge carriers on the electrochemical properties of organic quinone compounds remains unclear. Herein, we selecte a small molecule 9,10-anthraquinone as a study model and propose that the proton assisted metathesis reaction between anthrahydroquinone and Mn+ results in stabilizing electrode reaction. Meantime, the possibility of anthraquinone as anode for aqueous multivalent metal-ion (Al3+, Mg2+, Zn2+) batteries is illustrated. Typically for aluminum-ion battery, a reversible capacity of 211.4 mA h g-1 at 800 mA g-1 after 500 full cycles with a capacity retention of 94.5% can be obtained. This work may provide guidance to design and explore more organic quinone compounds for aqueous batteries.