Purification of graphene oxide dispersions by using a fluidic cell

Author(s)

Santos, Marcos Alves ^[1] ; Marques, Lucas ^[1] ; Castro Silva, Cecilia de Carvalho ^[1]

Affiliation

^[1] Univ Prebiteriana Mackenzie, MackGraphe Graphene & Nanomat Res Ctr, BR-01302907 Sao Paulo - Brazil

• Document type: Journal article
• Source: ANALYTICAL METHODS; v. 12, n. 28, p. 3575-3581, JUL 28 2020.
• Web of Science Citations: 0

Abstract

The purification process of graphene oxide (GO) is a key stage in the production of this two-dimensional material by the Hummers method. This step demands a large amount of water, energy and time. The inefficient removal of the contaminants present in GO may affect its properties and make it unfeasible for some applications, such as in the field of biology. Here, we develop a simple and efficient method for the purification of an aqueous GO dispersion based on a fluidic diffusion cell system with a porous nitrocellulose membrane. The effectiveness of the fluidic diffusion cell system was compared with that of traditional purification methods, such as dialysis and centrifugation. The proposed strategy achieves the best performance in the removal of the major contaminants (K((aq center dot))(+), Na((aq center dot))(+), Cl((aq center dot))(-), SO4(aq center dot)2-, Mn-(aq center dot)(2+) and MnO2(s)), demanding similar to 95% less water than dialysis and in a shorter time (similar to 23 h). The system operates under flow conditions, with minimum handling by the operator and is able to select the GO flakes with bigger lateral dimensions. This work represents a simple and fast alternative for purification of GO dispersions that can be easily scaled-up. (AU)

• FAPESP's process: 17/15143-2 - Combination of paper and nanomaterials in the development of anode and cathode electrodes for lithium-ion batteries
• Grantee: Lucas Marques
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 12/50259-8 - Graphene: photonics and opto-electronics: UPM-NUS collaboration
• Grantee: Antonio Helio de Castro Neto
• Support Opportunities: Research Projects - SPEC Program