Screening effect of CVD graphene on the surface free energy of substrates

Autor(es)

Costa, Mariana C. F. ^{[1, 2]} ; Parra, Gustavo G. ^[1] ; Larrude, Dunieskys R. G. ^[1] ; Fechine, Guilhermino J. M. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Prebiteriana Mackenzie, Mackenzie Inst Res Graphene & Nanotechnol MackGra, Rua Consolacao 896, BR-01302907 Sao Paulo, SP - Brazil

^[2] Natl Univ Singapore, Ctr Adv 2D Mat CA2DM, Singapore 117546 - Singapore

• Tipo de documento: Artigo Científico
• Fonte: Physical Chemistry Chemical Physics; v. 22, n. 29, p. 16672-16680, AUG 7 2020.
• Citações Web of Science: 1

Resumo

The wettability of graphene has been a topic under constant discussion in the literature since 2012. In this work we measured the contact angle (CA) of six different types of substrates (glass, quartz, Si3N4, Si/SiO2, sapphire and Si) with varying dielectric constants and surface roughnesses in order to calculate the surface free energy of graphene films to evaluate how the wetting properties of graphene-coated substrates are changed according to the underlying substrate. We used a residual-free transfer process to remove the high-quality graphene (CVD-Gr) grown onto copper foil. Afterwards, we performed an inert thermal treatment (Ar, at 300 degrees C for 30 minutes) to remove airborne contaminants from the graphene surface and evaluate the roughness of substrates by atomic force microscopy, the advancing and receding contact angles of two liquids (water and ethylene glycol), hysteresis, and surface free energy (polar and dispersive components) calculations. The presence of high-quality monolayer graphene (free of any air contaminants, polymer residues,etc.) led to a common wettability behaviour for all coated surfaces, regardless of the nature of the underlying substrate. This result can be understood in terms of the screening of van der Waals and dipole interactions by the electrons in graphene. (AU)

• Processo FAPESP: 12/50259-8 - Grafeno: fotônica e opto-eletrônica: colaboração UPM-NUS
• Beneficiário: Antonio Helio de Castro Neto
• Modalidade de apoio: Auxílio à Pesquisa - Programa SPEC
• Processo FAPESP: 14/22840-3 - Transferência direta a seco de grafeno-CVD para substratos poliméricos bidimensionais e tridimensionais
• Beneficiário: Guilhermino José Macêdo Fechine
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 16/22918-8 - Funcionalização não covalente de nanoestruturas 2D com moléculas orgânicas e nanopartículas de carbono: um sistema ternário para aplicação em energia
• Beneficiário: Gustavo Gimenez Parra
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado