Cyanide Bridged Framework Nanoplates Catalytic Interlayer for High Performance Zinc-Iodine Battery

Iodine is a promising candidate among the cathode materials in zinc-ion battery. However, iodine cathode suffers from serious shuttle effect by spontaneous generated polyiodide species. In this work, we developed a CoNi(CN)₄/CNT interlayer to prevent shuttle effect by adsorption-catalysis process. The adsorption of the iodine species on CoNi(CN)₄/CNT interlayer is justified by UV-vis spectroscopy and X-ray photoelectron spectroscopy, where the concentration of polyiodides is significantly reduced, and the binding energy of cobalt, nickel, and nitrogen is remarkably reduced by binding with polyiodides. The zinc-iodine dual-plating battery shows significantly higher areal capacity and cycle stability with CoNi(CN)₄/CNT. Moreover, battery with impressive areal capacity of 3.6 mAh cm⁻² and negligible fading over 100 cycles is also achieved, which outperforms state-of the art literatures on zinc-iodine batteries.