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

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