Graphene effects on the structural, morphological and optical properties of PEDOT:PSS thin films

Abstract

In this work, nanocomposite polymeric films were fabricated by spin coating technique on the pre-treated glass substrate for sensors application. nanocomposites consist of PEDOT:PSS polymer as a matrix phase and Graphene with different weight percentages (0.5, 1, 1.5, 2) wt% as a dispersion phase. To enhance its surface reactivity, glass substrate were etched chemically using Piranha Solution. FTIR results showed there is no chemical reaction occurred, just only hydrogen bonding arises among components. The mechanism of the proposed model suggested that the interaction achieved by three steps. XRD results showed that, with the Graphene content, the diffraction position shifted upward; from 2θ = 24° to 2θ = 26°, as well as the intensity increased. All crystalline parameters, which either derived from Bragg's Law or from Scherer's equation proved the Graphene dispersion and the increment of the crystallinity. AFM results showed that roughness increased by about 92% through the roughness average (Sa) parameter and by 45% through the density of summits (Sds) parameter. These finding matched with the SEM images, which showed that, the PEDOT:PSS films without Graphene has a comparatively smoother surface than the PEDOT: PSS with Graphene and this confirms that the mechanical strength of the prepared films improved clearly and significantly. UV‐ VIS Spectroscopy results proved that Graphene addition increased the absorbance in UV, VIS, and IR regions, and the absorbance in the UV region is higher than the other two regions, which indicates that the prepared film resists UV- degradation.