Regulating Sodium Deposition Behavior via Polar Functional Group-Based Interfacial Engineering on an Industrial-Scale Anode for High-Performance Na-CO2 Batteries.

The development of sodium-carbon dioxide (Na-CO2) batteries is crucial for renewable energy utilization and CO2 fixation. However, their practical application is severely hindered by Na dendrite formation coupled with aggressive CO2 electro-/chemical corrosion, and extremely low Na anode utilization rates. This study addresses these interconnected challenges by employing a multifunctional covalent organic framework (COF) coating. Specifically, the C6O6-TAPT COF features a fully conjugated skeleton for rapid electron cloud response, abundantly distributed sodiophilic chelation sites (C═O and C═N) for Na+ capture, and ordered AB stacked structure for homogenizing Na+ flux. The COMSOL simulations further demonstrate the stress-regulating strategy in mitigate solid electrolyte interphase (SEI) cracking and separator puncturing risks. Consequently, Na-CO2 batteries using the designed industrial-scale anode achieve low polarization (1.4 V) and sustain stable cycling for over 1100 h at 100 mA g-1 across 0-60 °C. Remarkably, it maintained over 100 cycles at reduced N/P of 10 and delivered a high discharge capacity of 11552 mAh g-1 under lean electrolyte conditions (8.7 µL mAh-1). This study validates stable and functionalized COF substrates with dendrite suppression capability in Na-CO2 batteries, proposing a scalable pathway with implications for next-generation energy storage.