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.