Silver nanowire arrays with high aspect ratios have been prepared using potentiostatic electrodeposition within the confined nanochannels of a commercial porous anodic aluminium oxide template. The nucleation and growth processes are intensively studied by current versus time transients. Scanning electron microscopy results show that the nanowires have a highly anisotropic structure with diameters and lengths of 170 nm and 58 µm, respectively, which coincide with the dimensions of the template used. Structural characterization using x-ray diffraction shows that the Ag nanowires are highly crystalline, and those obtained at higher overpotentials present a very strong [220] preferred crystallographic orientation. The optical properties of the silver nanowires embedded in the alumina template show a clear edge close to 320 nm, that is an expected value for a silver–alumina composite material.

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This paper examines the influence of electrodeposition potential, pore size, pH, composition, and temperature of the electrolytic bath on the structure of nickel nanowires arrays electrodeposited into anodic alumina oxide porous membranes. Scanning electron microscopy, X-ray diffraction, and transmission electron microscopy analysis were employed to characterize the structural and morphological properties of the nanowires. Results show that the electrodeposition potential controls the growth of nickel nanowires along some preferential crystallographic planes. At -0.90 V (vs. Ag/AgCl) single crystalline nanowires with a strong (111) orientation were obtained. High temperatures and a moderately acid pH solution contributed to improve the single crystalline character of nanowires. The presence of chloride ions produced polycrystalline nanowires at low temperature and single crystalline nanowires at high temperature. The influence of the electrodeposition potential in their magnetic anisotropies is also reported.

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In this work we report a simple and cost-effective CsPbBr 3based solar cell without ordinary selective contacts. To do so we follow an electrochemical approach consisting of three successive steps: (1) electrodeposition of PbO 2 directly on top of FTO substrates, (2) heterogeneous phase reaction with gaseous HBr and (3) spin-coating of methanolic CsBr solutions followed by annealing. This method is more adequate for largescale environmentally friendly production as it reduces chemical waste, particularly toxic lead. The resulting films were structurally and optically characterized showing good coverage of the FTO substrates, absence of defects such as pinholes and orthorhombic structure. Photovoltaic and impedance characterization was carried out by pressing a carbon coated metal spring onto the CsPbBr 3 film until obtaining maximized opencircuit potential (V oc) and short-circuit photocurrent density (j sc) under simulated sunlight. The stabilized current at fixed voltage (SCFV) technique gave a maximum PCE value of 2.70 % close to devices with similar configuration. Impedance measurements demonstrated analogous behavior to that of state-of-art CsPbBr 3 based solar cells, comprising a recombination arc at mid-high frequencies, geometrical capacitance and ideality factors closed to 2, typical of SRH recombination in the perovskite bulk.

This work shows a detailed study of the electrodeposition of Cu2O thin films from DMSO solution employing Cu(ClO4)2 and molecular oxygen as precursors. Through cyclic voltammetry experiences at different temperature, the potential interval where the electrodeposition of Cu2O is carried out was established. The films were obtained potentiostatically and were characterized through different techniques. The films were crystalline with a globular morphology showing a direct bandgap between 2.18 eV – 2.25 eV depending on the temperature of electrodeposition. All the films showed a p-type semiconductor character with a doping level varying between 8.2 × 1018 cm−3 – 2.0 × 1019 cm−3. This difference is attributed to the increase of the stoichiometric defects in the films with the operation temperature.