Homogeneous transfer of graphene oxide into photoresist: Fabrication of high surface area three-dimensional micro-arrays by modified photolithography

Herein, we studied the homogeneous transfer of graphene oxide (GO) into photocurable SU-8 photoresist for fabricating GO/SU-8 three-dimensional (3D) composite micropillar arrays by modified photolithography. SU-8 is a negative toned epoxy based photoresist, which includes 8 epoxy groups in each SU-8 monomer. The effects of the concentration of GO flakes on the thermal, mechanical and specific surface area (SSA) properties of the resultant composites were investigated. The large amount of oxygen functional groups on the GO plane and at the edges allowed uniform distribution of GO sheets within the SU-8 resin. The GO/SU-8 micropillar arrays were fabricated by a versatile ultraviolet (UV) photolithography technique that allowed the synthesis of various 3D micro-nano integrated carbon microelectrode arrays. The integrated GO flakes were bonded to the surface or embedded within the primary structure of SU-8 micro-pillars. These SU-8 micropillars having surface-bonded or embedded GO flakes showed superior thermal stability, strength, and SSA characteristics than bare SU-8 micropillars. Thus, this new synthesis approach provides a novel route for developing high performance catalysts, sensors, and adsorbents, among other materials.