This review article’s primary aim is to discuss different thin-film deposition technique methods and their important uses. The histories of thin-film technology, thin-film growth, thin-film classification, and thin-film preparation techniques are also covered in this review article. The preparation and characterization of functional thin films and nanostructured materials, as well as various devices based on these materials and recent developments are also focused on in this review. The properties of the materials and several thin-film deposition techniques are also covered in this article. This review article also discusses the classification and application of thin-film sensors. Furthermore, the formation of thin films and their physical properties are impacted by deposition conditions such as pH, temperature, deposition time, and deposition parameters, which are analyzed. This article discusses how a wide range of potential uses in structural, mechanical, and protective coatings; sensing; energy storage systems; catalysis; optoelectronics; and biomedicine are made possible by the special qualities of thin films and nanostructured materials, including their high surface area to volume ratio, structure, surface charge, anisotropic nature, and tunable functionalities.

In the current work, copper tungsten oxide (CuWO₄) nanoparticles are incorporated with carbon nanofiber (CNF) to form CNF/CuWO₄ nanocomposite through a facile hydrothermal method. The prepared CNF/CuWO₄ composite was applied to the electrochemical detection of hazardous organic pollutants of 4-nitrotoluene (4-NT). The well-defined CNF/CuWO₄ nanocomposite is used as a modifier of glassy carbon electrode (GCE) to form CuWO₄/CNF/GCE electrode for the detection of 4-NT. The physicochemical properties of CNF, CuWO₄, and CNF/CuWO₄ nanocomposite were examined by various characterization techniques, such as X-ray diffraction studies, field emission scanning electron microscopy, EDX-energy dispersive X-ray microanalysis, and high-resolution transmission electron microscopy. The electrochemical detection of 4-NT was evaluated using cyclic voltammetry (CV) the differential pulse voltammetry detection technique (DPV). The aforementioned CNF, CuWO₄, and CNF/CuWO₄ materials have better crystallinity with porous nature. The prepared CNF/CuWO₄ nanocomposite has better electrocatalytic ability compared to other materials such as CNF, and CuWO₄. The CuWO₄/CNF/GCE electrode exhibited remarkable sensitivity of 7.258 μA μM⁻¹ cm⁻², a low limit of detection of 86.16 nM, and a long linear range of 0.2–100 μM. The CuWO₄/CNF/GCE electrode exhibited distinguished selectivity, acceptable stability of about 90%, and well reproducibility. Meanwhile, the GCE/CNF/CuWO₄ electrode has been applied to real sample analysis with better recovery results of 91.51 to 97.10%.

The most frequently used sulfonamide is sulfamethazine (SMZ) because it is often found in foods made from livestock, which is hazardous for individuals. Here, we have developed an easy, quick, selective, and sensitive analytical technique to efficiently detect SMZ. Recently, transition metal oxides have attracted many researchers for their excellent performance as a promising sensor for SMZ analysis because of their superior redox activity, electrocatalytic activity, electroactive sites, and electron transfer properties. Further, Cu-based oxides have a resilient electrical conductivity; however, to boost it to an extreme extent, a composite including two-dimensional (2D) graphitic carbon nitride (g-C₃N₄) nanosheets needs to be constructed and ready as a composite (denoted as g-C₃N₄/Cu₂Y₂O₅). Moreover, several techniques, including X-ray diffraction analysis, scanning electron microscopy analysis, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and Raman spectroscopy were employed to analyze the composites. The electrochemical measurements have revealed that the constructed g-C₃N₄/Cu₂Y₂O₅ composites exhibit great electrochemical activity. Nevertheless, the sensor achieved outstanding repeatability and reproducibility alongside a low limit of detection (LOD) of 0.23 µM, a long linear range of 2 to 276 µM, and an electrode sensitivity of 8.86 µA µM⁻¹ cm⁻². Finally, the proposed GCE/g-C₃N₄/Cu₂Y₂O₅ electrode proved highly effective for detection of SMZ in food samples, with acceptable recoveries. The GCE/g-C₃N₄/Cu₂Y₂O₅ electrode has been successfully applied to SMZ detection in food and water samples.