Publications by authors named "Johan Ek Weis"

Fluorination modifies the electronic properties of graphene, and thus it can be used to provide material with on-demand properties. However, the thermal stability of fluorinated graphene is crucial for any application in electronic devices. Herein, X-ray photoelectron spectroscopy (XPS), temperature-programmed desorption (TPD), and Raman spectroscopy were used to address the impact of the thermal treatment on fluorinated graphene.

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Fluorination of graphene opens up a bandgap, which creates opportunities for optoelectronics, and also paves the way for the creation of extremely thin insulating layers, which can be important for applications in devices. However, in spite of many interesting features offered by, for example, unequally doped layers in multilayered systems, most of the work has concerned the fluorination of graphene monolayers. Here, the fluorination process of graphene bilayers is investigated through high-resolution Raman mapping followed by analysis of more than 10,000 spectra of bilayer graphene.

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One of the greatest issues of nanoelectronics today is how to control the heating of the components. Graphene is a promising material in this area, and it is essential to study its thermal properties. Here, the effect of heating a bilayer structure was investigated using in situ Raman spectroscopy.

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The electromechanical properties of arrays of vertically aligned multiwalled carbon nanotubes were studied in a parallel plate capacitor geometry. The electrostatic actuation was visualized using both optical microscopy and scanning electron microscopy, and highly reproducible behaviour was achieved for actuation voltages below the pull-in voltage. The walls of vertically aligned carbon nanotubes behave as solid cohesive units.

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