Zinc-iodine (Zn-I) batteries are promising energy storage devices because of relatively high capacity, non-flammable aqueous electrolyte, eco-friendliness and low cost. However, the shuttle effect of polyiodides has severely caused rapid capacity decay. Herein, an interconnected conductive cobalt phthalocyanine/carbon nanotubes (CoPc@CNT) cathode was prepared for adsorbing iodine species and further catalyzing the conversion of polyiodides to inhibit the shuttle effect in Zn-I batteries. In situ Raman tests combined with theoretical calculation demonstrate that CoPc decreases the overall conversion energy barriers and accelerates conversion of polyiodides to improve the cycling stability. As a result, Zn-I batteries deliver an ultra-long cycle stability for 9500 cycles with a high-capacity retention of 94 % at a high current density of 20 mA cm. The Zn-I pouch battery assembled with CoPc-loaded carbon fiber cathode achieves a high specific capacity of 9.1 mAh cm. In addition, the designed dual-layer series Zn-I pouch battery normally operates with the charge/discharge voltage platform of 2.33 V. This work broadens the application of CoPc and explores a novel catalytic pathway for polyiodides conversion.

中文翻译：

---

用于高性能锌碘电池的催化钴酞菁/碳纳米管正极


锌碘（Zn-I）电池由于容量相对较高、水性电解质不易燃、环境友好且成本低廉，是一种很有前景的储能装置。然而，聚碘化物的穿梭效应严重导致容量快速衰减。在此，制备了互连导电钴酞菁/碳纳米管（CoPc@CNT）阴极，用于吸附碘物种并进一步催化聚碘化物的转化以抑制锌-I电池中的穿梭效应。原位拉曼测试结合理论计算表明，CoPc降低了整体转化能垒，加速了聚碘化物的转化，从而提高了循环稳定性。因此，Zn-I 电池可提供 9500 次循环的超长循环稳定性，在 20 mA cm 的高电流密度下，容量保持率为 94%。与负载 CoPc 的碳纤维正极组装的 Zn-I 软包电池实现了 9.1 mAh cm 的高比容量。此外，设计的双层串联Zn-I软包电池通常在2.33 V的充放电电压平台下运行。这项工作拓宽了CoPc的应用，并探索了多碘化物转化的新催化途径。