title: Graphene Nanobubbles Produced by Water Splitting.
abstract: Graphene nanobubbles are of significant interest due to their ability to trap mesoscopic volumes of gas for various applications in nanoscale engineering. However, conventional protocols to produce such bubbles are relatively elaborate and require specialized equipment to subject graphite samples to high temperatures or pressures. Here, we demonstrate the formation of graphene nanobubbles between layers of highly oriented pyrolytic graphite (HOPG) with electrolysis. Although this process can also lead to the formation of gaseous surface nanobubbles on top of the substrate, the two types of bubbles can easily be distinguished using atomic force microscopy. We estimated the Young's modulus, internal pressure, and the thickness of the top membrane of the graphene nanobubbles. The hydrogen storage capacity can reach ∼5 wt % for a graphene nanobubble with a membrane that is four layers thick. The simplicity of our protocol paves the way for such graphitic nanobubbles to be utilized for energy storage and industrial applications on a wide scale.
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: Hongjie
authors.identifier: 0000-0003-4095-1751
authors.initials: H
authors.lastname: An
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: Beng Hau
authors.initials: BH
authors.lastname: Tan
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: James Guo Sheng
authors.initials: JGS
authors.lastname: Moo
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: Sheng
authors.initials: S
authors.lastname: Liu
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: Martin
authors.identifier: 0000-0001-5846-2951
authors.initials: M
authors.lastname: Pumera
authors.affiliation: Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.
authors.forename: Claus-Dieter
authors.initials: CD
authors.lastname: Ohl
keywords: Graphene nanobubbles; atomic force microscopy; electrochemistry; energy storage; hydrogen; water splitting