Low-Valent Cu ^I O Stabilized by a Layered Vanadium Oxide: Potential Reversal and Physicochemical Iodine-Anchoring for Synergistic Cu/V/I Conversions

↔ 2 CuI can occur spontaneously to achieve the synergistic redox of copper and iodine with improved kinetics. And this strategy of "physical confinement", "chemical conversion" and "synergistic redox" can immobilize iodine physicochemically and accomplish multielectron transfer of Cu/I/V, leading to a coupled battery with a high voltage output, but circumventing the generation of unstable high-valent iodine species.