Low total electron yield graphene coatings produced by electrophoretic deposition

• Published in: Applied surface science 2020-02, Vol.504, p.143870, Article 143870
• Main Authors: Aguincha, R., Bundaleski, N., Bundaleska, N., Novaković, M., Henriques, J., Rakočević, Z., Tatarova, E., Teodoro, O.M.N.D.
• Format: Article
• Language: English
• Subjects: Electrophoretic deposition; Graphene; Secondary electron yield; XPS
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.143870

[Display omitted] •Electrophoretic deposition of graphene on copper and stainless steel was performed.•Properties of the free-standing graphene are very similar to those of the deposits.•Total electron yield of deposited surfaces was reduced from ~2.2 to ~1.0.•Such surfaces may be of high relevance for both accelerator and space technologies. Stainless steel and copper technical substrates have been coated by free standing graphene using electrophoretic deposition technique, with the final goal to obtain chemically inert low secondary electron emission surfaces. This class of materials is of utmost interest in future accelerators in order to increase further the flux of accelerated charged particles in the beam. The measured maximum total electron yield of pristine graphene, which has been previously characterized by electron microscopies and X-ray photoelectron spectroscopy, appears to be about 1.0. The deposition parameters have been optimized in order to obtain surfaces with lowest total electron yield, but also composition and morphology close to that of pristine graphene. When applying these optimized deposition parameters graphene coatings on two substrates, i.e. stainless steel and copper, the maximum total electron yield of about 1.04 was obtained. The composition of coatings and the relative amounts of sp2 bonds are slightly worse than those of the pristine graphene, while the surface morphology appears to be the same. Annealing at 150 °C for 64 h in high vacuum, showed that vacuum baking did not affect considerably the electron emission properties of the coatings.