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The purpose of this work is to study the influence of the annealing temperature on the structural, morphological, compositional and optical properties of CuSbSe2 thin films electrodeposited in a single step. CuSbSe2 thin films were grown on fluorine-doped tin oxide (FTO)/glass substrates using the aqueous electrodeposition technique, then annealed in a tube furnace under nitrogen at temperatures spanning from 250 to 500 °C. The resulting films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis, Raman spectroscopy and UV-Vis spectrophotometer. The annealing temperature plays a fundamental role on the films structural properties; in the range 250–350 °C the formation of pure CuSbSe2 phase from electrodeposited binary selenides occurs. From 400 to 500 °C, CuSbSe2 undergoes a preferential phase orientation change, as well as the increasing formation of copper-rich phases such as Cu3SbSe3 and Cu3SbSe4 due to the partial decomposition of CuSbSe2 and to the antimony losses.

Self-polarized ferrimagnetic nanowires of CoFe2O4 are electrochemically grown by the electrodeposition technique in AAO membranes. XRD, EDS and SQUID analysis confirm the formation of highly stoichiometric CoFe2O4 nanowires with high magnetic response into 20 nm-AAO membrane. SEM and AFM images revealed a total filling of the AAO membrane with Co and Fe at an applied potential of −1.2 V. In addition, the electrodeposition and cooling in the presence of an applied magnetic field improve the magnetic response of CoFe2O4 nanowires. The SQUID measurements confirmed the elaboration of CoFe2O4 nanowires with an internal magnetic field of 1.52 T. As a result, this ferrimagnetic nanowired substrate will be suitable for future miniaturized self-biased microwave devices.

The present paper examines the influence of an applied magnetic field B (AMF B) on the physical and chemical properties of electrodeposited Cobalt (Co) and Nickel (Ni) nanowires into anodic aluminum oxide (AAO) membranes. The deposition potential and the effect of the AMF B on the mass transport rate of Ni and Co ions to the bottom of the pores were examined using cyclic voltammetry (CV) and current density–time curves. X-ray diffraction (XRD) studies show that the AMF B promotes the growth of Co and Ni into the membrane pores. The AMF B effect on the morphology and chemical composition of the electrodeposited nanowires were studied by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDXS), respectively. Co nanowires exhibit a high coercive field H c , shape anisotropy, and squareness ratio M M s than those corresponding to Ni nanowires.

Well-crystallized CoFe2O4 nanowires are grown by electrodeposition into anodic alumina oxide (AAO) membrane. The XRD and EDS analysis confirmed the synthesis of pure CoFe2O4 with average grain size ranging from 30 to 22 nm. The SQUID investigations revealed that the nanowires electrodeposited at −1.2 V exhibit a large remanent magnetization and high permanent internal magnetic field along the wire axis. The microwave studies emphasized a gyromagnetic resonance around 42 GHz. In addition, numerical simulations performed by HFSS showed good agreement with experimental results. As a consequence, such electrodeposited nanocomposite is a promising candidate for high-frequency microwave devices.

Spinel oxides synthetized by the electrochemical route can be used in different technological areas. In the present work, cobalt ferrite (CoFe2O4) thin films were deposited from sulfate bath on FTO-coated glass substrate by linear sweep voltammetry technique (LSV). We have investigated the effect of applied magnetic field B (AMF B) up to 0.5 T on the electrochemical response, the crystallographic texture, the morphology, the semiconductor type and the optical properties of the elaborated films. The structural and compositional analysis confirmed the synthesis of a well-crystallized CoFe2O4 with a good stoichiometry after an annealing treatment at 500 °C. Moreover, the CoFe2O4 films exhibited a p-type semiconductor as confirmed by the photo-electrochemical and Mott-Schottky tests. In addition, an increasing in the absorbance in the visible-UV region is observed under AMF B. Consequently, the magneto-electrodeposited CoFe2O4 thin films have a direct band gap energy of 1.5 eV.

Eco-friendly lead-free perovskite CH3NH3SnI3 (MASnI3) based solar cell device was simulated using the one-dimensional solar capacitance tool (SCAPS 1D). In this work, we investigate the effect of several parameters such as the thickness and the defect density in the absorber layer. We focus on the effect of defect densities at the TiO2/MASnI3, MASnI3/Spiro-OMeTAD interfaces on the photovoltaic performances. Our results show that the best performances were obtained with an absorber thickness layer kept of 1.1 μm, and for low defect densities in the active layer and at the TiO2/MASnI3 interface. In addition, we have studied the effect of various hole transport layers (HTL) compounds such as Cu2O, CuO, CuI, CuSCN, PTAA, PEDOT: PSS, and MEH-PPV. Our results show the significant impact of valence band offset and hole mobility on device performances. The champion device has a power conversion efficiency of 27.77%, a current density (J sc) of 34.6 mA cm−2, an open circuit voltage (V oc) of 0.96 V and a fill factor of 83.34%. This work can provide imperative guidelines to researchers for the design of efficient eco-friendly perovskite solar cells.

In this work, we report the application of highly efficient electrodeposited cobalt ferrite (CoFe2 O4 ) thin films in electrochemical degradation of rhodamine B. XRD, FTIR and Raman spectroscopic studies confirmed the formation of single phase CoFe2 O4 . SEM analysis revealed a very fine nanorods dispersed uniformly with average size around 30 nm. UV-Vis spectrophotometry emphasized that the optical band gap value is 1.6 eV. Moreover, the elaborated CoFe2 O4 thin films showed a good efficiency for the electrochemical degradation of an aqueous solution of rhodamine B (RhB) attaining 99% during the first 3 min of reaction time. The trapping experiments revealed that the hydroxyl radicals were the main active species leading to the removal of RhB initial concentration of 10 mg/L in a very short time. PRACTITIONER POINTS: A simple electrodeposition technique was used to fabricate CoFe2 O4 thin. XRD and FTIR studies revealed the formation of pure cubic spinel phase. Nano-rod like morphology has been successfully synthesized. The rhodamine B aqueous solution has been completely decolorized using the obtained CoFe2 O4 thin films.

CuSbSe2 belongs to the Copper antimony chalcogenides CuSbCh 2 (Ch=S,Se). An emerging family of absorbers studied for thin-film solar cells. CuSbSe2 thin films have been prepared by electrodeposition in one-step followed by the annealing process in tubular furnace at 300°C for 5min under N2 atmosphere. The reduction potentials region was determined by cyclic voltammetry and linear sweep voltammetry. Then the samples have been deposited by chronoamperometry at different potentials during 1h. The structural, morphological and optical properties of CuSbSe2 thin films were studied by X-ray diffraction, SEM and spectrophotometer respectively.

Cobalt-copper (Co-Cu) granular nanowire arrays were electrochemically prepared into Anodic Aluminum Oxide (AAO) membranes. We demonstrate that the application of a magnetic field B (MF B) during the synthesis of nanowires leads to control their chemical and physical properties. XRD studies have shown polycrystalline nanowires. Their morphology and chemical composition were studied by scanning electron microscope (SEM) and energy dispersive X-ray spectrometry (EDXS). The results showed that the nanowire diameters vary between 200 and 240 nm. In addition, the magnetic field changes the elemental percentage of cobalt and copper into the membrane pores. The AFM images show that the magneto-electrodeposited sample have a higher surface roughness. SQUID studies indicate that the nanowires electrodeposited under MF B have a coercive field Hc of 800 Oe and a squareness ratio Mr/Ms of 0.31.

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