Heterostructural Graphene Quantum Dot/MnO2 Nanosheets toward High-Potential Window Electrodes for High-Performance Supercapacitors.

ABSTRACT: The potential window of aqueous supercapacitors is limited by the theoretical value (≈1.23 V) and is usually lower than ≈1 V, which hinders further improvements for energy density. Here, a simple and scalable method is developed to fabricate unique graphene quantum dot (GQD)/MnO2 heterostructural electrodes to extend the potential window to 0-1.3 V for high-performance aqueous supercapacitor. The GQD/MnO2 heterostructural electrode is fabricated by GQDs in situ formed on the surface of MnO2 nanosheet arrays with good interface bonding by the formation of Mn-O-C bonds. Further, it is interesting to find that the potential window can be extended to 1.3 V by a potential drop in the built-in electric field of the GQD/MnO2 heterostructural region. Additionally, the specific capacitance up to 11

SUBMITTER: Jia H 

PROVIDER: S-EPMC5979621 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature