Described herein are aqueous organic redox flow batteries that include a first redox active material that can include a metallocene or a salt thereof, and a second redox active material that can include a viologen or a salt thereof. The aqueous organic redox flow batteries may further include a first aqueous electrolyte, a second aqueous electrolyte, and a separator between the first and second aqueous electrolytes. In addition, disclosed herein are methods of making the metallocene and viologen compounds.