A new supercapacitor based on manganese oxide could combine the storage capacity of batteries with the high power and fast charging of other supercapacitors. By combining manganese oxide with cobalt manganese oxide, a heterostructure is formed in which interfacial properties can be tuned.
The group started with simulations to see how manganese oxide’s properties change when coupled with other materials. When they coupled it to a semiconductor, they found it made a conductive interface with a low resistance to electron and ion transport. This will be important because otherwise the material would be slow to charge.
Combining manganese oxide with cobalt manganese oxide as a positive electrode and a form of graphene oxide as a negative electrode yields an asymmetric supercapacitor with high energy density, remarkable power density, and excellent cycling stability.
By scaling up the lateral dimensions and thickness, the material has the potential to be used in electric vehicles. The next step will be to tune the interface where the semiconducting and conducting layers meet for better performance. The team will add the supercapacitor to already developed flexible, wearable electronics and sensors as an energy supply for those devices or directly as self-powered sensors.