Synthesis and characterization of semiconducting Zinc Oxide (ZnO) nanofibers

This work focused on the fabrication of electrospun nanofibers from a solution of polyvinyl alcohol (PVA) and zinc nitrate to obtain zinc oxide (ZnO) nanofibers through calcination. Structural, morphological, and electrical characterizations were carried out using Raman spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), atomic force microscopy (AFM), and the potentiostat's current-voltage (C-V) linear potentiostatic function. Raman spectroscopy and XRD showed characteristic peaks that confirmed the formation of ZnO starting at a calcination temperature of 500 °C. FTIR analysis identified functional groups and molecular structures of both PVA/zinc nitrate nanofibers and ZnO nanofibers. SEM revealed that the 4% solution is ideal for synthesis, as it produced a large quantity of nanofibers with more uniform diameters. TGA analysis showed that PVA/zinc nitrate nanofibers have thermal stability starting at 450 °C, while pure PVA has stability starting at 500 °C. AFM analysis estimated that the PVA/zinc nitrate nanofibers before calcination have diameters between 1500 and 2000 nm, which are reduced by 90% after calcination, with diameters between 120 and 380 nm for ZnO nanofibers. Electrical measurements showed that the calculated resistance in FTO substrates with PVA/zinc nitrate nanofibers and ZnO nanofibers increases as electrospinning time increases.

• מחבר ראשי: Pomaquiza Castillo, Sergio Israel (author)
• פורמט: bachelorThesis
• שפה: eng
• יצא לאור: 2024
• נושאים: Nanofibras electrohiladas; Alcohol polivinílico; Medidas eléctricas; Electrospun nanofibers; Polyvinyl alcohol; Electrical measurements
• גישה מקוונת: http://repositorio.yachaytech.edu.ec/handle/123456789/848