This paper reports the successful synthesis of spinel‐type CuFe ₂ O ₄ ferrite nanoparticles with an average particle size of 24 nm, produced using the citrate sol–gel autocombustion method. The structure of the synthesized material was analyzed through x‐ray diffraction (XRD) and further supported by Raman and FT‐IR spectroscopy. The analysis confirmed that the material formed a spinel ferrite structure with the Fd3m space group. Valence states and energy levels of the elements were examined using x‐ray photoelectron spectroscopy (XPS). Surface morphology was studied using scanning electron microscopy (SEM), coupled with elemental analysis. The magnetic properties of the synthesized CuFe ₂ O ₄ ferrite nanoparticles were investigated using a vibrating sample magnetometer (VSM). Magnetization measurements revealed that the sample exhibited characteristic magnetic parameters of copper ferrite, with a saturation magnetization (Ms) of 23.10 emu/g, a coercivity Hc of 415 Oe, and a remnant magnetization (Mr) of 12.80 emu/g. These magnetic properties enable efficient magnetic separation of the nanoparticles from aqueous solutions, thereby enhancing process efficiency and minimizing catalyst loss during photocatalytic applications. Optical and photocatalytic properties were investigated using spectrophotometry, revealing an optical band gap of 1.85 eV, which demonstrates potential for photocatalytic activity under visible light. The CuFe ₂ O ₄ ferrite effectively degraded dyes such as methylene blue (MB), malachite green (MG), Safranine (S), Congo Red (CR), and Rhodamine B (RhB) within 180 min, highlighting its practical application potential. The study identified that hydroxyl radicals (·OH), generated from H ₂ O ₂ decomposition under visible light irradiation, played a critical role in enhancing the efficiency of the photo‐Fenton reaction. A proposed mechanism involves the excitation of CuFe ₂ O ₄ under visible light, facilitating electron transfer that leads to the generation of ·OH radicals, which degrade the dye molecules. Among the tested dyes, CR exhibited the highest degradation percentage with a rate constant of 0.033 min⁻ ¹ and followed a pseudo‐first‐order kinetic model. The effect of hydrogen peroxide concentration on dye degradation efficiency was also evaluated.

This study presents the synthesis, characterization and magnetic properties of of Cu₁₋ₓNiₓFe₂O₄ nanocrystalline ferrites (0.0 ≤ х ≤ 1.0) using the sol-gel autocombustion method at a neutral pH. The samples were characterized by X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), vibrating sample magnetometry (VSM) and Mossbauer spectroscopy. The structural analysis confirmed the formation of mixed spinel structures, with crystallite sizes ranging from 22-32 nm. Mössbauer spectra of ⁵⁷Fe were recorded at room temperature (300K) and liquid nitrogen temperature (77K), and variations in line width, isomer shift, quadrupole splitting, and hyperfine magnetic field magnitudes were calculated for both tetrahedral and octahedral sublattices. The cation distribution, revealed through XRD, VSM and Mössbauer spectroscopy, shows a consistent pattern with nickel ions predominantly occupying octahedral sites. The magnetic properties were modified by substituting nickel ions with copper ions, affecting the distribution of magnetic Fe3+ ions and the total magnetization. The maximum saturation magnetization and coercivity reached 59.54 emu/g and 327.8 Oe, respectively. These findings reveal a systematic modification of magnetic properties through nickel substitution, resulting in enhanced saturation magnetization and coercive force. Notably, the synthesized samples exhibit sufficiently high magnetic properties, making them suitable for practical applications such as magnetic hyperthermia, a promising therapeutic approach for cancer treatment. The nanoparticles can be designed to generate heat in response to an alternating magnetic field, allowing for targeted and controlled heating of tumor cells.

This study explores the synthesis and characterization of magnesium-substituted copper ferrite (Mg_xCu_1-xFe₂O₄, 0.0≤x≤1.0) nanoparticles using the polymer-assisted sol–gel self-combustion method. The effects of magnesium substitution on the structural, elastic, and magnetic properties of the ferrites were systematically investigated. X-ray diffraction (XRD) analysis confirmed the formation of single-phase cubic spinel structures with particle sizes ranging from 8–21 nm. A slight increases in the lattice parameter was observed with higher magnesium content, attributed to the substitution of smaller Cu²⁺ ions with slightly larger Mg²⁺ ions. Fourier Transform Infrared (FTIR) spectroscopy and Mössbauer spectroscopy revealed the spinel structure and complex magnetic interactions between ferromagnetic and superparamagnetic phases. The spin canting was observed and found to vary significantly across compositions, with a maximum canting angle of 58.47°. This notable result highlights the important magnetic behavior of these materials. The saturation magnetization (M_S) varied across samples, with the x = 0.6 composition exhibiting optimal magnetic performance. Cation distribution analysis using XRD, Mössbauer spectroscopy, and magnetic measurements consistently showed the redistribution of cations between the tetrahedral (A) and octahedral (B) sites in the spinel structure. This research demonstrates the potential of magnesium-substituted copper ferrites for magnetic applications, with notable improvements in magnetic and structural properties due to cation substitution.

This study numerically investigates the optimization of P3HT/Si hybrid solar cells for maximum efficiency via numerical simulation using SCAPS ID. The analysis identifies P3HT layer thickness and Si donor density as critical parameters, with optimal values of 20 nm and 10¹⁷ cm⁻³, respectively. Exceeding these values leads to decreased efficiency due to reduced hole mobility, increased recombination, and enhanced absorption loss. Furthermore, minimizing defect density in Si is crucial for achieving high efficiency. The optical properties of the P3HT/Si hybrid thin film were investigated using the transfer matrix method (TMM), yielding exceptional transmittance (94.5%), low reflectance (4.5%), and minimal absorption (1.0%) at a wavelength of 0.5876 μm. This highlights the material’s potential for efficient and transparent photovoltaic devices. By optimizing these parameters, a maximum efficiency of ∼24% was achieved, demonstrating the potential for high-performance hybrid solar cells. This work underscores the significance of numerical analysis in designing efficient hybrid solar cells, paving the way for the development of low-cost, high-performance devices via spin coating, a groundbreaking advancement in solar energy harvesting.