Biogelatin-Derived and N,S-Codoped 3D Network Carbon Materials Anchored with RuO₂ as an Efficient Cathode for Rechargeable Li–O₂ Batteries

The practical application of the lithium–oxygen battery is still restricted by a cathode with a low specific capacity and a poor cycle stability. In this work, we prepared ruthenium dioxide nanoparticle (RuO₂NP)-supported gelatin-derived porous doped carbon (GPDC) catalysts with different contents of RuO₂ by a facile and effective sol–gel and low-temperature heat treatment. Benefiting from the large specific surface area and porous structure, the RuO₂/GPDC catalyst with 15 wt % RuO₂ exhibits an excellent cathode performance with a high specific capacity of 10751 mAh g^–1 and a long-term cyclic stability of 306 cycles at 100 mA g^–1. The experimental results demonstrate that the abundant channel structure provides enough space for the storage of discharge products and the addition of RuO₂NPs significantly improves the reversibility of the electrodes with excellent OER activity. Furthermore, the existence of RuO₂ NPs tunes the morphology and distribution of discharge products to affect the discharge capacity. This work may provide a pathway to resolving the existing problems of Li–O₂ batteries.