MOF-derived Bi₂O₃@C microrods as negative electrodes for advanced asymmetric supercapacitors

Bismuth oxide (Bi₂O₃) with high specific capacity has emerged as a promising negative electrode material for supercapacitors (SCs). Herein, we propose a facile metal-organic framework (MOF) derived strategy to prepare Bi₂O₃ microrods with a carbon coat (Bi₂O₃@C). They exhibit ultrahigh specific capacity (1378 C g^-1 at 0.5 A g^-1) and excellent cycling stability (93% retention at 4000 cycles) when acting as negative electrode material for advanced asymmetric SCs. The assembled Bi₂O₃@C//CoNi-LDH asymmetric supercapacitor device exhibits a high energy density of 49 W h kg^-1 at a power density of 807 W kg^-1. The current Bi-MOF-derived strategy would provide valuable insights to prepare Bi-based inorganic nanomaterials for high-performance energy storage technologies and beyond.