This study presents the synthesis and characterization of TiN hard coatings as a candidate reference material for surface metrology in chemistry. TiN coatings were grown on a silicon wafer with (111) orientation using dc reactive magnetron sputtering. X-ray diffraction confirms that the diffraction phase of TiN coatings is polycrystalline, electron microscopy demonstrates that the TiN coatings presents pyramidal-shaped grains ranging from sub-micrometer to nano-size scale and with an average thickness of 666 nm. According to micro Raman results, the presence of LO phonon modes confirms that the TiN coatings are crystalline in nature and no impurities are detected. The mechanical properties at the nanoscale are evaluated using resonance tracking acoustic force atomic microscopy. The chemical composition of the TiN reveals a close 1:1 atomic ratio. The ANOVA is used to evaluate the homogeneity of the TiN via a homogeneity test according to the ISO Guide 35:2017, while, regarding the chemical composition of the Ti, the Fisher’s test demonstrates that the batch can be considered as homogeneous.

We introduce a fully solution-processed interlayer strategy for n–p CdS/PbS thin film solar cells that combines a sol–gel ZnO compact coating with an electrospun ZnO nanofiber network. The synthesis and characterization of ZnO, CdS, and PbS thin films, complemented by electrospun ZnO nanofibers, are aimed at low-cost photovoltaic applications. Sol–gel ZnO films exhibited a hexagonal wurtzite structure with a bandgap (Eg) of approximately 3.28 eV, functioning effectively as electron transport and hole-blocking layers. CdS films prepared by chemical bath deposition (CBD) showed mixed cubic and hexagonal phases with an Eg of about 2.44 eV. PbS films deposited at low temperature displayed a cubic galena structure with a bandgap of approximately 0.40 eV. Scanning Electron Microscopy revealed uniform ZnO and CdS surface coatings and a conformal 1D ZnO network with nanofibers measuring about 50 nm in diameter (ranging from 49.9 to 53.4 nm), which enhances interfacial contact coverage. PbS films exhibited dense grains ranging from 50 to 150 nm, and EDS confirmed the expected stoichiometries. Electrical characterization indicated low carrier densities and high resistivities consistent with low-temperature processing, while mobilities remained within reported ranges. The incorporation of ZnO layers and nanofibers significantly improved device performance, particularly at the CdS/PbS heterojunction. The device achieved a V_oc of 0.26 V, an J_sc of 3.242 mA/cm², and an efficiency of 0.187%. These improvements are attributed to enhanced electron transport selectivity and reduced interfacial recombination provided by the percolated 1D ZnO network, along with effective hole blocking by the compact film and increased surface area. Fill-factor limitations are linked to series resistance losses, suggesting potential improvements through fiber densification, sintering, and control of the compact layer thickness. This work is a proof-of-concept of a fully solution-processed and low-temperature CdS/PbS architecture. Efficiencies remain modest due to low carrier concentrations typical of low-temperature CBD films and the deliberate omission of high-temperature annealing/ligand exchange. Overall, this non-vacuum, low-temperature coating method establishes electrospun ZnO as a tunable functional interlayer for CdS/PbS devices and offers a practical pathway to elevate power output in scalable productions. These findings highlight the potential of nanostructured intermediate layers to optimize charge separation and transport in low-cost PbS/CdS/ZnO solar cell architectures.

This work investigates the effect of high-energy mechanical milling on the activation and phase transformation of synthetic pseudoboehmite powders. The approach aims to provide a clean, solvent-free route with potential industrial relevance for alumina production. Mechanical processing proved effective in inducing the transition from pseudoboehmite to χ-Al₂O₃ solely through milling. The process yielded nanometric particles with low levels of contamination. The subsequent conversion to α-Al₂O₃ was achieved through controlled heat treatments, while phase evolution was monitored by differential scanning calorimetry (DSC). A reduction of approximately 110 °C in the α-Al₂O₃ formation temperature was observed after 30 h of milling. This shift was accompanied by a marked decrease in the activation energy, from 526 kJ·mol⁻¹ for the raw powder to 347 kJ·mol⁻¹ for the milled sample. These results demonstrate the strong mechanochemical activation of pseudoboehmite, highlighting mechanical milling as an effective and scalable route for energy-efficient processing of alumina phases.

The incorporation of copper and oxygen into zinc telluride (ZnTe) thin films deposited by radio-frequency magnetron sputtering from a single ZnTe–CuO composite target was investigated. The nominal Cu and O concentrations ranged from 3 to 13 atom %, and films were grown at substrate temperatures of 300 and 350 °C. Energy-dispersive X-ray spectroscopy confirmed controlled compositional transfer from the target to the films. X-ray diffraction analysis revealed that all films are polycrystalline, exhibiting a coexistence of zinc blende and wurtzite ZnTe phases. Low dopant concentrations produced only minor lattice modifications, while higher Cu and O contents promoted the formation of Cu _{2− x} Te secondary phases, as confirmed by Raman spectroscopy, grazing-incidence X-ray diffraction and scanning electron microscopy. Optical measurements showed a significant reduction in infrared transmittance with increasing Cu concentration, attributed to the metallic-like absorption of Cu _{2− x} Te phases. Electrical characterization revealed a transition from semiconducting to highly conductive behavior with resistivity decreasing from approximately 10 ² to 10 ⁻² Ω·cm for films grown at 300 °C and from 10 ¹ to 10 ⁻³ Ω·cm for films grown at 350 °C. Simultaneously, the carrier concentration increased from approximately 10 ¹⁷ to 10 ²¹ cm ⁻³ and the mobility from 10 ⁻¹ to 10 ¹ cm ² ·V ⁻¹ ·s ⁻¹ . These results indicate that structural, optical, and electrical properties of ZnTe are primarily influenced by Cu incorporation and the formation of conductive Cu-rich secondary phases, yielding a biphasic system composed of semiconducting ZnTe and conductive Cu-rich telluride phases. These material properties suggest potential relevance for future studies of back-contact materials in CdTe-based solar cells.