Interfacial Electronic Nanoarchitectonics for Sustainable Zn─I ₂ Batteries

Abstract Aqueous zinc‐iodine batteries (AZIBs) are intrinsically safe and cost‐effective, yet their performance is limited by sluggish iodine redox kinetics, poor conductivity, and severe polyiodide shuttling. Herein, we design a heterostructure cathode by depositing titanium nitride (TiN) onto biomass‐derived porous nitrogen‐doped carbon (PNC), forming a tailored PNC@TiN interface that markedly enhances electronic conductivity and regulates iodine electrochemistry. Density functional theory (DFT) calculations reveal pronounced interfacial charge redistribution with an upward shift of the Ti d ‐band centeri, enabling strong Ti─I bonding through orbital coupling among Ti 3 d , C/N 2 p , and I 5 p states, as well as improved iodine affinity with suppressed polyiodide shuttle. Accordingly, the AZIB with the PNC@TiN cathode exhibits a high reversible capacity of 166.9 mAh g −1 after 21,000 cycles at 2.0 A g −1 (95.4% retention), and exceptional durability over 66,000 cycles at 5.0 A g −1 with an ultralow capacity decay of 0.00028% per cycle. Furthermore, the as‐assembled pouch cells achieve 176.1 mAh g −1 with negligible degradation, highlighting their practical viability. This work underscores the crucial role of interfacial electronic nanoarchitectonics in modulating iodine chemistry, and presents a sustainable strategy to repurpose biomass into advanced energy‐storage materials.