Super gas barrier and selectivity of graphene oxide-polymer multilayer thin fims
Thin films made by branched polyethylenimine (PEI) and graphene oxide (GO) using Layer-by-layer (LbL) deposition in aqueous suspensions are studied on the focus of oxygen barrier. Linear thickness and mass growth were observed with 4.3 ~ 5.0 nm per bilayer. AFM and TEM images showed the discrete nanobrick wall structure and polydispersed graphene sheets. A 30 bilayer PEI/GO film, with a 149 nm thickness, decrease the oxygen transmission rate by a factor of 45 and obtained an oxygen permeability within the same order of magnitude as a SiOx coating (6.6 × 10-20 cm3 (STP) · cm/cm2 · s · Pa). This impressive gas barrier makes it a promising alternative to currently used materials for flexible electronics and food packaging.
Yang, YH; Bolling, L; Priolo, MA; Grunlan, JC; Adv. Mater, 2013, 25, 503-508.
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