Metal organic framework-derived MnO@carbon composites for highly durable Li-ion batteries and hybrid electrochemical cells

Exploring structurally stable and high-capacity metal oxides with carbon-based composite have attracted great attention in energy storage devices. Herein, we demonstrate gram scale synthesis of manganese oxide encap-sulated carbon (MnO@C) nanofoil composite using the simple thermolysis of manganese metal organic frame-work (Mn-MOF) under inert atmosphere. The encapsulated MnO nanoparticles on carbon nanofoils enable higher electrochemical conductivity and extended durability as an electrode material for Li-ion batteries and super-capacitors (SCs). Specifically, the prepared MnO@C nanofoil composite delivers a reversible capacity of 1083 mAh g(-1) for MnO@C, which is higher than the pristine Mn2O3 (889 mAh g(-1)) at a current density of 500 mA g(-1) after 100 cycles. The MnO@C nanofoil composite also exhibits much better specific capacity of 771 mAh g(-1) at a high current density of 2000 mA g(-1) with the retention rate of 89% after 800 cycles. Furthermore, as a battery-type electrode for hybrid SCs, the MnO@C nanofoil composite shows higher capacitance and energy/power densities of 46.7 F g(-1) and 15.9 Wh kg(-1)/4356.3 W kg(-1) with excellent cycling durability. The cost-effectively synthesized MOF-derived composites could be utilized as promising materials in the development of long-term energy storage devices.

Automated summary

In this study, gram scale synthesis of manganese oxide encapsulated carbon nanofoil composite was demonstrated. The composite showed higher electrochemical conductivity and extended durability, making it a promising electrode material for Li-ion batteries and super-capacitors. The composite also exhibited better specific capacity and higher capacitance and energy/power densities, making it suitable for long-term energy storage devices.