Laser‐Induced Ultrafine Cu‐Anchored 3D CNT‐rGO Carrier for Flexible and Durable Zinc‐Iodine Micro‐Batteries

Abstract Three‐dimensional (3D) carbon materials are often used as carriers for anchoring iodine in zinc‐iodine batteries (ZIBs). However, the physical stacking of carbon materials during the electrode assembly process, the weaker physical interactions between non‐polar carbon materials and iodine species, and the scarcity of catalytic sites for iodine conversion led to a reduced catalytic activity for the iodine redox reaction, which fails to completely inhibit the shuttling of iodine species. Here, 3D ultrafine Cu‐anchored CNT‐rGO carriers (3D Cu@CNT‐rGO) with interconnected structures are prepared using a simple laser‐induced reduction strategy. The 3D microporous structure and excellent electrical conductivity of 3D Cu@CNT‐rGO make it an ideal host for iodine. Ultrafine Cu nanoparticles introduce as catalysts accelerate the redox kinetics, efficiently catalyze iodine/polyiodide conversion, inhibit polyiodide shuttling, and enhance the electrochemical performance of ZIBs. The fabricated zinc‐iodide micro‐batteries (ZIMBs) delivers a high specific area capacity of 1.29 mAh cm −2 , a high area energy density (1.55 mWh cm −2 ) and a high area power density (33.58 mW cm −2 ) as well as excellent cyclin stability (80% capacity retention after 4000 cycles). Meanwhile, ZIMBs have excellent mechanical flexibility and have great potential for application in the field of integrated, miniaturized and flexible electronic devices.