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ZnMgO semiconductor is of major interest in sustainable thin‐film solar cells in order to replace buffer layers based on nonabundant or toxic elements. In addition, it has the potential 1) to allow optimal band alignment with absorbers such as CIGS, CZTS, and Cu2O; 2) to have high transparency; 3) to have adjustable properties for use as a window or buffer layer; and 4) to be deposited using low‐cost and energy‐efficient techniques such as ultrasonic spray pyrolysis. This study focuses on modulating ZnMgO properties with the optimization of the ultrasonic spray pyrolysis and post‐annealing parameters. Optical transmission, X‐ray diffraction, and van der Pauw/Hall effect measurements are used to study the material properties. Thin films with a strong <002> preferred orientation are obtained with large crystallite size (42–80 nm), high transparency (>90%), a bandgap increase from 3.28 to 3.34 eV with magnesium composition and annealing, an optimal Urbach energy of 0.068 eV, and electrical properties modulated by magnesium composition and annealing with resistivity varying from 6.520 Ωcm down to 0.022 Ωcm and a carrier concentration from 4.8 × 1017up to 1.4 × 1020cm−3. ZnMgO as an alternative thin film material using only Earth‐abundant and nontoxic elements. Ultrasonic spray pyrolysis: low‐cost and scalable technique to optimize growth. Post‐annealing and magnesium composition: modulate optical and electrical properties. Strong <002> orientation, high transparency (>90%), and modulable bandgap are between 3.28 and 3.34 eV. Modulable resistivity is between 6.520 and 0.022 Ωcm.

ZnMgO thin films are elaborated by ultrasonic spray pyrolysis using water‐based solutions only, for an Mg composition as high as 70 mol%. The elaboration conditions are optimized and the structural, optical, and electrical properties of the ZnMgO films are investigated with respect to the Mg concentration using X‐Ray fluorescence, X‐Ray diffraction, atomic force microscopy, Raman and transmission spectroscopies, and van der Pauw/Hall effect electrical measurements. The obtained properties are correlated to analyze the miscibility and, for single‐phase material, the optoelectronic, optical, and transport properties with respect to the composition. The elaborated thin films exhibit a monotonous increase in the bandgap, a high transparency above 90% in the visible region, and a dramatic decrease in the n‐type carrier concentration, for Mg compositions lower than 30 mol% where wurtzite single‐phase structure is evidenced. A compensation mechanism of the n‐type dopants in ZnO, attributed to interstitial Zn which acts as a shallow donor, is given as an explanation of this variation of the carrier concentration. These optoelectronic properties show that ZnMgO can be efficiently used in applications such as UV detectors and solar cells. The optimized elaboration of ZnMgO was performed using ultrasonic spray pyrolysis with Mg miscibility of 30%. The transmission of the ZnMgO films was above 90%. The carrier concentration decreases due to the bandgap modulation from 3.26 to 3.65 eV and inhibition of shallow donors. The ZnMgO properties can be exploited for detectors and all‐oxide solar cells.

Conducting polymer composites, which are simply physical mixtures of an insulating polymer matrix and intrinsically conducting polymers, are promising new materials for various applications such as antistatic coatings, shielding and electromagnetic absorbers. In this context, a novel conducting composite was successfully produced. It is based on epoxy resin and polyaniline (PANI) doped in benzene sulfonic acid, which was used as conducting filler. The effect of PANI loading levels on the structural, morphological, thermal, electrical and dielectric properties was explored using techniques, such as Raman, Fourier transform infrared and ultraviolet-visible-NIR spectroscopy, X-ray diffraction, atomic force microscopy, scanning electron microscopy, thermogravimetric analysis and differential scanning calorimetry. The electrical behavior and morphology of the synthesized PANI revealed disorder and defects. In addition, as the applied voltage is increased, the current through the sample increases rapidly. The conductivity and dielectric properties were also investigated at room temperature in the frequency range of 1?MHz–1?GHz. The dielectric constant was shown to increase with increased loading at low frequencies and then decreases rapidly, reaching a constant value at higher frequencies. In addition, the AC conductivity of the prepared composites increases with the addition of PANI and is higher at high frequencies. Furthermore, the stability of the composites was found to be influenced by increasing the amount of PANI filler in the matrix.