C 60 /Na 4 FeO 3 /Li 3 V 2 (PO 4 ) 3 /soft carbon quaternary hybrid superstructure for high-performance battery-supercapacitor hybrid devices

To develop battery-supercapacitor hybrid devices with high energy and power densities, we propose a rational design of a quaternary hybrid superstructure by using a high-energy biotemplate. This new superstructure is composed of stable fullerene C60 nanocages, electroactive Na4FeO3, high-energy Li3V2(PO4)3 and soft carbon as well as tubular ordered mesoporous channels. This design takes advantage of the unique properties of each component, resulting in nanocomposites with synergistic effects to improve the charge transfer and energy storage. We found that this quaternary hybrid electrode has both high energy and power densities as well as a long cycling life in a Li/Na mixed-ion electrolyte, outperforming a multitude of other battery-supercapacitor hybrid devices reported thus far. The charge storage mechanisms of this hybrid superstructure are proposed for optimizing the electrode design. An energy-storage device that has the advantages of both batteries and supercapacitors has been developed by researchers in China and Sweden. Batteries can store a lot of energy in a small space: they have a high energy density. Supercapacitors, on the other hand, can be more quickly charged and discharged: they have a high power density. Wen He from the Qilu University of Technology in Jinan, Jiefang Zhu from Uppsala University and their colleagues have created a hybrid energy-storage device that has both high energy density and high power density. Their device uses a wide range of different materials combining carbon nanocages, soft carbon, and the electroactive material Na4FeO3. This design takes advantage of the unique properties of each component, resulting in improved charge transfer and energy storage. Achieving both high energy and high power densities in one hybrid energy-storage device is highly challenging, yet critically important for many applications. Here, the authors demonstrate that the inherent limitations of batteries and supercapacitors can be solved by developing a quaternary hybrid superstructure electrode using a high-energy biotemplate.