We have transferred CVD-grown graphene onto SiO2. Atomic force microscopy revealed that the surface is characterized by folds, whose height may reach several nm. Onto such surface we have evaporated pentacene. Preferential nucleation has been observed at the sites of fold intersection.
COBISS.SI-ID: 2603515
Organic thin-film transistor transfer characteristics and time-of-flight (TOF) photoconductivity measurements were used to investigate the effect of the addition of liquid-phase exfoliated graphene nanoflakes (GNs) on the electron mobility in thin films of N,N′-bis(1H,1H-perfluorobutyl)dicyanoperylenecarboxydiimide (PDIF-CN2). Transfer characteristics measurements reveal that the charge carrier mobility of PDIF-CN2 increases by almost 3 orders of magnitude via blending with GNs. TOF photocurrent measurements confirm that the GNs improve the charge carrier transport in PDIF-CN2.
COBISS.SI-ID: 3614971
Atomic force microscopy has been used to examine early stages of pentacene growth on exfoliated single-layer graphene transferred to SiO2 substrates. We have observed 2D growth with mean height of 1.5 ± 0.2 nm on as-transferred graphene. Three- dimensional islands of pentacene with an average height of 11 ± 2 nm were observed on graphene that was annealed at 350 °C prior to pentacene growth.
COBISS.SI-ID: 3574011
The optical absorption of graphene was obtained from spectroscopic ellipsometry in the visible and ultraviolet range. Measured spectra were analyzed by optical models based on the Fresnel coefficients. The optical models were supported by Raman, scanning electron microscopy, and atomic force microscopy measurements. Our results show that a residue layer left on graphene can significantly increase its optical absorption in the visible range.
COBISS.SI-ID: 2864123
Using atomic force microscopy we have examined morphology of sub-monolayer thick pentacene layers, deposited on exfoliated single-layer and bilayer graphene, transferred onto SiO2. We observe two-dimensional island growth in the range of substrate tempera- tures from 10 to 60 °C. We find that island size distributions on single-layer graphene are broader and centered at higher average island areas than on bilayer graphene.
COBISS.SI-ID: 2987003