Fabrication of biomimetic graphene films on fabric base by two-beam laser interference

Abstract

Through millions of years of evolution and natural selection, various biological species own unique physiological structure and amazing functionality. Biomimetic fabrication demonstrate remarkable trend of development, artificial biomimetic materials and intelligent functional surfaces have been extensively studied by scientists both theoretically and experimentally. In general, traditional biomimetic materials consisting of metal, metal oxides, carbon materials and some other polymer materials, which make outstanding contribution to the generation and development of engineering bionics science and interface chemistry analysis. However, simpleminded traditional materials are not capable to deal with the presence of intelligent driving control and micro nano device applications in artificial biomimetic science. It is well established that the combination of novel materials and novel biomimetic technology may lead to promote progress and development of fabrication with smart integration of multifunctional biomimetic devices. More recently, a kind of carbon nanomaterials with an atomic layer thickness which named graphene has attracted most widely attention due to its excellent properties, for instance ultrahigh carrier mobility, good electrical conductivity, high transmittance and biocompatibility since it has been founded by mechanical stripping adhesive tape, it becomes a new star of materials scientific fields. Its stable physical/chemical properties make it widely applied in electronic devices, optical devices, biochips, and even intelligent robots. Based on graphenes distinctive material properties, micronano-structured graphene surfaces with special wettability may be fabricated in a biomimetic manner that not only contribute to the experimental research but also bring about a new revolution of graphene-devices. A method of fabrication of biomimetic graphene surface with multilevel-structures by two-beam laser interference system has been proposed. Graphene oxide films on different fabric bases have been reduced and ablated by Nd:YAG laser interference system. Periodic graphene micronano-structures with grating-like micro structures and additional nanoscale structures have been produced during laser processing process with appropriate laser power (0.4 W), which resulted in deoxidization of abundant hydrophilic oxygen containing groups (OCGs) on GO sheets. To original GO film, the reduced GO (RGO) surface not only exhibited more rough geometry, but also owned lower surface energy. Raman spectroscopy has been characteristiced, the result of the D and G band peaks of RGO show neglectable changes contrast GO. The reason is that the laser cutting and ablation can bring additional new defects on the edges of graphene sheets, which leads to the increase of D band peak. As a result, the spectra show unobvious changes. Roughness of the fabric surface (silk, cotton, nylon) further increased the surface roughness of biomimetic graphene surface. Graphene biomimetic surface with multi-structures has been formed by the double action of rough fabric base and graphene micronano-structure. The graphene bionic surface with nylon substrate has the largest hydrophobic angle, ~156°. The biomimetic graphene surface not only possesses superhydrophobic wettability, but also exhibits rainbow structural color due to the existence of periodic graphene micronano-structures. We believe that the biomimetic graphene surface on fabric substrate will not only have important application prospects in the field of bionics, but also be a major exploration and breakthrough in the future research of optoelectronic and wearable devices.