title: Gel-derived cation-π stacking films of carbon nanotube-graphene complexes as oxygen cathodes.
abstract: A key challenge in processing carbon nanotubes and their composites for large-scale applications is aggregation. Cation-π stacking interactions have been discovered to disperse heavily entangled single-walled carbon nanotube (SWNT) bundles in ionic liquids (ILs). In this work, we found that a dispersible, silky single-layer graphene (SLG) can be readily gathered together to form a crosslinked gel after entrapping sufficient IL molecular via the likely noncovalent interaction. By incorporating the dispersed SWNTs into the gathered SLG gel synchronously, we prepared solid, finely crosslinked SWNTs-SLG films, assisted by an avenue of 2-step extraction to remove the IL completely. The gel-derived SWNTs-SLG complex film was applied as a support material of oxygen cathodes for Li-O2 batteries. It exhibited a remarkable improved cycleability in comparison to made of SWNTs and SLG alone due to the finely crosslinked feature. Decorated SWNTs and SLG can also form gel-derived complexes via the same process to construct support-catalyst complexes. A SWNTs-SLG film loaded with Ru nanoparticles exhibited not only catalytic effects, but also the ability to suppress the side reactions, and hence stabilized the whole Li-O2 battery. Our research introduces a gel-derived, high-dispersed processing of carbon nanotube-graphene complexes and demonstrates their favorable applications on Li-O2 batteries.
authors.affiliation: Energy Technology Research Institute, National Institute of Industrial Science and Technology (AIST), Umezono 1-1-1, Tsukuba, Ibaraki 305-8568 (Japan).
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Matsuda
authors.forename: Haoshen
authors.initials: H
authors.lastname: Zhou
mesh_terms: D002384:Catalysis; D011211:Electric Power Supplies; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D052578:Ionic Liquids; D037742:Nanotubes, Carbon; D006108:Graphite
keywords: Li-O2 batteries; carbon nanotubes; cation-π stacking interaction; gels; graphene