Synthesis of a Graphene-Like Nanofilm from Polyacrylonitrile.

There are various different approaches in synthesizing graphene including chemical vapor deposition (CVD) and solid-phase method, where gas or solid type carbon source, to be converted into graphene, interacts with transition metals such as nickel and copper. When any thin nickel layer coated atop the polyacrylonitrile (PAN) film is pyrolyzed at a sufficiently high temperature, it is impossible to grow a continuous graphene film with a large area owing to dewetting, which has restricted the subsequent utilization in practical applications. Herein, we suggest a method to synthesize a continuous graphene-like nanofilm with a nickel coated thin PAN film through pyrolysis at 750 to 800 °C in a high-vacuum furnace without a reductive gas flow.

Synthesis of flake-like graphene from nickel-coated polyacrylonitrile polymer.

Graphene can be synthesized from polyacrylonitrile (PAN) polymer through pyrolysis. A metal catalyst such as nickel (Ni) is required for the conversion of the polymer to graphene. The metal catalysts can be placed either atop or underneath the polymer precursor.

Micropatterning of cells on electron-irradiated poly(dimethylsiloxane) surface.

In this study, a facile route to fabricate micropatterns of cells is presented on the basis of electron irradiation of poly(dimethylsiloxane) (PDMS). PDMS films were irradiated with electron beams through a pattern mask with micrometer-sized grids. After irradiation, the changes in the chemical composition, morphology, and wettability of the PDMS surface were investigated by using an X-ray photoelectron spectrometer, an atomic force microscope, and a contact anglometer.

Patterning of TiO2 particles on poly(dimethyl siloxane) films by using proton irradiation and liquid-phase deposition process.

Micropatterning of titanium dioxide (TiO2) on the surface of thin poly(dimethyl siloxane) (PDMS) films was described by means of proton irradiation and liquid-phase deposition (LPD) techniques. The surface of thin PDMS films was irradiated with accelerated proton ions through a pattern mask in the absence or presence of oxygen in order to create hydrophilically/hydrophobically patterned surfaces. The results of the surface analysis revealed that the PDMS films irradiated at the fluence of 1 x 10(15) ions cm-2 in the presence of oxygen showed the highest hydrophilicity.