Synthesis and characterization of electrospun CuO nanofibers and the influence of calcination temperature

This work focuses on fabricating and characterizing copper oxide (CuO) nanostructured fibers synthesized via electrospinning using polyvinylpyrrolidone (PVP) and copper acetate as precursors, with optimized electrospinning parameters (voltage: 6 kV, flow rate: 1 mL/hr). The fibers underwent an annealing process at five different calcination temperatures to evaluate the phase transformations and morphological evolution of the fibers as the temperature increased. These calcination temperatures were 400, 500, 600, and 700 °C. PVP decomposed completely at 450 °C, according to thermogravimetric analysis (TGA), with fiber stabilization starting at 500 °C. Raman spectroscopy confirmed the formation of CuO at 400 °C, with characteristic vibrational peaks at 285 cm−1, 600 cm−1, and 635 cm−1, and their intensities increasing at higher temperatures. In comparison, at 600 °C, X-ray diffraction (XRD) demonstrated enhanced crystallinity and phase purity, with monoclinic CuO exhibiting dominant peaks at the (002), (111), and (200) planes. Fourier-transform infrared (FTIR) spectroscopy showed that all functional groups associated with the polymer had been completely eliminated after calcination. PVP evaporation significantly reduced the fiber diameter, as con-firmed by atomic force microscopy (AFM), with an average diameter of 1.56 m at 600 °C. Fluorescence microscopy analysis revealed that the microstructure of CuO-based fibers has a porous film morphology and distinct fiber visibility under a blue filter. These outcomes suggest that 600 °C is the optimal calcination temperature for producing stable and well-crystallized CuO based on the structure of nanofibers. Indeed, this metal oxide structure makes them promising candidates for sensing and electronic applications.

• المؤلف الرئيسي: Osorio Sampedro, Nathaly Lisbeth (author)
• التنسيق: bachelorThesis
• منشور في: 2025
• الموضوعات: Materiales semiconductores; Electrohilado; Temperatura de recocido; Semiconductor materials; Electrospinning; Annealing temperature
• الوصول للمادة أونلاين: https://repositorio.yachaytech.edu.ec/handle/123456789/973