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This study presents synthesis by the Pechini method and characterization of Bi1−xGdxFeO3 powders (0.00 ≤ x ≤ 0.20), providing new insights into the effects of gadolinium substitution on the structural, magnetic, and thermal properties of BiFeO3. Unlike previous studies, this work identifies a previously unreported double structural transition, from rhombohedral to cubic symmetry at x = 0.10, and from cubic to orthorhombic symmetry for x ≥ 0.15, demonstrating the critical role of Gd concentration. The magnetization measurements at room temperature exhibited enhanced ferromagnetic-like behavior, with potential implications for improving the material's photocatalytic and multiferroic performance. Additionally, differential scanning calorimetry emphasized the material's thermal stability. These findings contribute to a deeper understanding of how Gd substitution modifies the properties of BiFeO3, offering potential for optimizing applications in energy storage, spintronics, and catalysis. [ABSTRACT FROM AUTHOR]

CuSbSe2 is a promising absorber nano-material for thin-film solar cells, for its attractive photovoltaic properties, low cost, and environmentally friendly constituent elements. In this work, the interest was focused on the investigation of the effect of three types of substrates (FTO, ITO, and Mo) and deposition time on the characteristics of the electrodeposited films and on the efficiency of the CuSbSe2-based PV cells. The adopted architecture for this is the typical of substrate/CuSbSe2/CdS/i-ZnO/Al-ZnO. XRD reveals that CuSbSe2 thin films deposited on different substrates are grown in orthorhombic CuSbSe2 chalcostibite form (JCPDS: 98-041-8754), all with 65 nm crystallite size. However, the deposition time affects their preferential directions. SEM-EDX analysis shows that the sample deposited on ITO (45 min) has an almost stoichiometric composition with the lowest impurity content. Despite this, the FTO-based solar cell (60 min) shows the best efficiency (0.51%), compared to the ITO-based cell (0.12%), due to higher Jsc values. [ABSTRACT FROM AUTHOR]

Herein the growth mechanism of an un-doped zinc oxide (i-ZnO) and an Al-doped zinc oxide (AZO) was investigated using electrochemical techniques. Zinc and aluminum nitrates precursors were used in an aqueous bath solution, under a fixed potential of about –1.0 V, at 80°C. The variations of the morphological, structural, and optical properties of AZO were investigated in terms of Al3+ concentrations ranging from 0 to 4 atomic percentage in the starting solution. The X-ray diffraction patterns showed the hexagonal wurtzite structure for all samples. The effect of the lateral growth mechanism of AZO instead of the longitudinal growth process of ZnO was confirmed by calculating the texture coefficient and by studying the surface morphology under high magnification via scanning electron microscopy. It was found that the morphology evolved from hexagonal flat nanorods into a mixture of tapered hexagonal nanorods and nanosheets, to larger nanosheets by adding aluminum ions dopants. All films demonstrated a transmittance of about 80% in the visible range and exhibited a slight red shift in the absorption edge with Al3+ doping. The optical band gap of AZO nanosheets was found to be lower than that of i-ZnO nanorods. These findings provide fundamental understanding of the growth mechanism and shape control of a nanostructured zinc oxide. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Potentiostatic and in situ electrochemical impedance spectroscopy (EIS) measurements were recorded to study the nucleation and growth mechanisms of electrodeposited Cu 2 NiSnS 4 (CNTS) thin films from aqueous solution at different applied potentials. The electrodeposition process of Cu-Ni-Sn-S precursors were studied using cyclic voltammetry and chronoamperometry techniques. The nucleation and growth mechanism of these films was found to follow a three-dimensional progressive nucleation limited by diffusion-controlled growth. The nucleation mechanism is found to be influenced by the presence of S 2 O 3 2- , which prompts the electrodeposition of S. In situ electrochemical impedance spectroscopy (EIS) investigates the electrodeposition behavior of CNTS precursors on the surface electrode. A capacitive behavior was observed at high frequencies, while the presence of Warburg diffusion was detected only for potentials less negative than -1.0 V vs. Ag/AgCl. The crystallographic structure, morphology, composition, and optical band gap of CNTS thin films was examined using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and UV-visible spectroscopy. Electrodeposition at -0.98 V vs. Ag/AgCl resulted in the formation of microsheets with a uniform morphology and homogeneous thickness of sulfurized CNTS film. This potential also proved to be optimal for achieving higher crystallinity, a pure phase, and a suitable band gap energy of approximately 1.6 eV., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

This study investigates the impact of lithium doping on the structural and photophysical properties of spin-coated CsPbBr 3 perovskite thin films. The deposited films display a pristine structure, preferentially growing along the (220) direction, and exhibit high-quality green photoluminescence at around 530 nm. The doping leads to an improvement in the optical properties of the films, as evidenced by a stronger photoluminescence (PL) intensity compared to undoped CsPbBr 3 , particularly at temperatures below 200 K. The increase in PL intensity suggests a decrease in defects and surface passivation. Additionally, the decrease in the power-law exponent β from 1.6 to 1.0 indicates a reduction in non-radiative recombination, likely due to trap states filling with free electrons induced by the doping. Overall, doping with lithium reduces non-radiative recombination, fills trap states, and reduces band tail/activation energy, leading to improved optoelectronic properties of the films. This investigation provides insights into the photophysical properties of the Li-CsPbBr 3 absorber layer and the recombination mechanism, and helps to unravel new methods for the development of high-stability, high-performance perovskite thin-film solar cells and optoelectronic devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The increasing CO 2 concentration in the atmosphere has caused profound environmental issues such as global warming. The use of CO 2 as a feedstock to replace traditional fossil sources holds great promise to reduce CO 2 emissions. The electrochemical conversion of CO 2 has attracted much attention because it can be powered by renewable sources such as solar energy. In this review article, we provide insight into the important parameters when studying CO 2 RR and give a comprehensive review on the description of synthesis methods with electrocatalytic CO 2 reduction over bimetallic copper-based materials. Due to the important bibliographic data on Cu bimetallic materials, we have limited this review to Sn, In, Pd, Zn and Ag. At the end of this review, challenges and perspectives for further upgrading have been included to briefly highlight the important future considerations of this rapidly growing technology., Competing Interests: The author declares that he has no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

In this study, we demonstrate that the crystallization process of CsPbI 2 Br films can be modulated when small amounts of additives are added to the precursor solution, leading to the formation of the bright brownish α-phase perovskite films with high orientation along the [100] crystallographic direction. Doped CsPbI 2 Br films exhibit improved crystallinity, with high coverage, large grain size and pinhole-free surface morphology, suitable for making high performance optoelectronic devices. We also explored the role of Cl in the photophysical properties of CsPbI 2 Br perovskite films using the temperature dependent photoluminescence technique. We found that the Cl ions enhance the photoluminescence emission by reducing the density of trap states, and also decrease the exciton binding energy from (22 ± 3) meV to (11 ± 2) meV. We believe this work contributes to understanding the effect of doping on the crystallization process with an in-depth insight into the photophysical properties of the cesium-based perovskite materials., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)