Polycrystalline Cu7Te4 Dendritic Microstructures Constructed by Spherical Nanoparticles: Fast Electrodeposition, Influencing Factors, and the Shape Evolution

Polycrystalline Cu7Te4 dendritic microstructures were successfully synthesized via a simple galvanostatic electrochemical deposition method at room temperature, employing a mixed solution containing Cu(CH3COO)(2), Na2TeO3, and nitric and as the electrolyte. Cu7Te4 dendrites were deposited at the current of 16 mA for 5 min. The phase and morphology of the as-prepared product were characterized by means of powder X-ray diffraction (XRD), energy-dispersive spectrometry (EDS), (high-resolution) transmission electron microscopy (HR/TEM), and scanning electron microscopy (SEM). Some factors influencing the formation of dendritic Cu7Te4 microstructures were systematically investigated, including the depositing currents, complexants, surfactants, original amounts of Cu(CH3COO)(2), and Cu2+ ion sources. Experiments showed that the low deposition current and the concentration of Cu(CH3COO)(2) were unfavorable for the formation of dendritic Cu7Te4 microstructures constructed by nanoparticles. A time-dependent shape evolution of polycrystalline Cu7Te4 dendrites was studied.