Laser direct writing of microstructure on graphene oxide/metal oxide hybrid film

Abstract

A conductive microstructure consisting of a reduced graphene oxide (rGO) and Cu was prepared by laser direct writing. A hybrid film on a polymer substrate was prepared from a water-dispersion mixture of graphene oxide (GO) and CuO nanorods (CuO NRs) by doctor blade method. A CW 405 nm blue-violet laser beam was scanned on the GO/CuO NRs hybrid film through an objective lens to prepare a microstructure of rGO/Cu on a flexible substrate. The reduction of CuO NRs to Cu was observed by micro-Raman spectroscopy. The surface resistivity of a laser scanned hybrid film was lowered with decreasing laser scan spacing. A hybrid film consisting of rGO/Cu microstructure showed a negative temperature coefficient of resistance (-1.18%/oC), which was extremely larger than those of usual carbon materials. Such characteristics can be applied to an IR photosensor.