Laser-Assisted Simultaneous Patterning and Transferring of Graphene

The patterning of graphene has gained a great deal of attention for practical applications such as electrical devices and sensors. Here we introduce a facile, versatile, and direct patterning method for the fabrication of electrically conductive graphene patterns on a flexible plastic substrate based on the laser transmission welding technique. One of the distinctive features of the developed technique is that both the patterning and transferring processes take place simultaneously with a simple laser treatment. Selective absorption of laser and localized melting by laser-induced heat were exploited to achieve a completely isolated pattern, occurring at the interface between a laser-absorbent graphene film and a laser-transparent plastic substrate. Graphene oxide (G-O) film was treated in the same way, resulting in a reduced G-O (RG-O) pattern. In this case, deoxygenation of functional groups in G-O arose together with the patterning and transferring. We found that the intensity and the scanning rate of laser irradiation considerably affected the size and chemical structures of the pattern. Scanning electron microscopy and Raman spectroscopy were used to measure the changes of the laser-treated G-O patterns.