In situ study of copper electrodeposition on a single carbon fiber

Copper metallization on carbon surface can improve physicochemical performances of carbon based materials and introduce multi-functionalities. This paper reports on the combined electrochemical characterization, in situ X-ray diffraction and fluorescence research, and scanning electron microscopic studies of nucleation and growth of Cu on individual carbon fibers. Compared to the flat glassy carbon substrates and Au thin film substrates, the onset potential of Cu electrodeposition on individual carbon microfiber is more negative with lower efficiencies, indicating the difficulty of Cu nucleation on carbon fiber surface. Utilizing the capability of synchrotron X-ray microbeam diffraction and fluorescence spectroscopy techniques, real time Cu crystalline structure and composition evolvement information during the electrochemical reaction processes have been studied. In situ study reveals random Cu grain formation and anisotropic growth. Dynamic Cu growth and dissolution were found to occur simultaneously during deposition. Cu nuclei density and size can be effectively controlled, in addition to the grain morphology and stability, indicating the possibility of electrochemical manipulation of microstructure thus the properties of Cu coated carbon materials.