π-Conjugated Metal Free Porphyrin as Organic Cathode for Aluminum Batteries

Nowadays, Al (dual) batteries are mainly based on graphite cathode materials. Besides this material, the limited life cycle and the rate performance of other possible cathode materials have hampered the development of practical and sustainable rechargeable aluminium batteries (RABs). Herein, we report an organic A4-metal-free porphyrin system bearing diphenylamimo-phenyl functional units as an Al-storage cathode material, which is capable of delivering a reversible capacity of 83 mAhg⁻1 at 1 Ag⁻1 after 200 cycles and displays a good cycling stability. Achieving such high rate performance opens a pathway to developing practical sustainable cathodes for aluminium batteries.