Solution-Processed Graphene/MnO2 Nanostructured Textiles for High-Performance Electrochemical Capacitors

• Published in: Nano letters Vol. 11; no. 7; pp. 2905 - 2911
• Main Authors: Yu, Guihua, Hu, Liangbing, Vosgueritchian, Michael, Wang, Huiliang, Xie, Xing, McDonough, James R, Cui, Xu, Cui, Yi, Bao, Zhenan
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 13.07.2011
• Subjects: Capacitance; Capacitors; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Devices; Electrochemistry; Electrodes; Energy storage; Exact sciences and technology; Fullerenes and related materials; diamonds, graphite; Graphene; Graphite - chemistry; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Manganese Compounds - chemistry; Materials science; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Nanostructures - chemistry; Nanotechnology; Nanotubes; Nanotubes, Carbon - chemistry; Oxides - chemistry; Particle Size; Physics; Solutions; Specific materials; Surface Properties; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Textiles; MnO2; textile; solution process; electrochemical capacitors; graphene nanosheets; Nanosheet; Electrolyte solution; Capacitors; Porous materials; Energy density; Electrode material; Nanostructures; Carbon; Singlewalled nanotube; Manganese oxides; Electrochemical properties; Aqueous solutions; Graphene; High energy; Sodium sulfate; Capacitance; Electrodeposition; Electrolytes; Active material; Nanostructured materials; Environmental protection
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl2013828

Large scale energy storage system with low cost, high power, and long cycle life is crucial for addressing the energy problem when connected with renewable energy production. To realize grid-scale applications of the energy storage devices, there remain several key issues including the development of low-cost, high-performance materials that are environmentally friendly and compatible with low-temperature and large-scale processing. In this report, we demonstrate that solution-exfoliated graphene nanosheets (∼5 nm thickness) can be conformably coated from solution on three-dimensional, porous textiles support structures for high loading of active electrode materials and to facilitate the access of electrolytes to those materials. With further controlled electrodeposition of pseudocapacitive MnO2 nanomaterials, the hybrid graphene/MnO2-based textile yields high-capacitance performance with specific capacitance up to 315 F/g achieved. Moreover, we have successfully fabricated asymmetric electrochemical capacitors with graphene/MnO2-textile as the positive electrode and single-walled carbon nanotubes (SWNTs)-textile as the negative electrode in an aqueous Na2SO4 electrolyte solution. These devices exhibit promising characteristics with a maximum power density of 110 kW/kg, an energy density of 12.5 Wh/kg, and excellent cycling performance of ∼95% capacitance retention over 5000 cycles. Such low-cost, high-performance energy textiles based on solution-processed graphene/MnO2 hierarchical nanostructures offer great promise in large-scale energy storage device applications.