Effect of Calcination Temperature on the Sol-Gel Synthesis of Aluminum-Doped ZnO Nanoparticles for Photovoltaic Applications

Abstract This study investigates the synthesis and characterization of zinc oxide (ZnO) nanoparticles doped with 3% aluminum (Al) for photovoltaic applications. The ZnO nanoparticles were synthesized using the sol-gel technique and subsequently calcined at 400°C, 500°C, and 600°C. X-ray diffraction (XRD) analysis confirmed the formation of ZnO nanoparticles with a hexagonal wurtzite crystal structure. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images revealed that the nanoparticle size increased with higher calcination temperatures. Energy-dispersive X-ray spectroscopy (EDX) confirmed the presence and homogeneous distribution of Zn, O, and Al within the samples. Fourier-transform infrared (FTIR) spectroscopy identified the presence of ZnO across all samples. Furthermore, the optical properties of the doped ZnO nanoparticles exhibited temperature dependent variations in absorbance, reflectance, and transmittance within the UV and Visible-IR spectra. The observed optical gap energies correlated with the calcination temperatures, suggesting a relationship between temperature, gap energy, and nanoparticle size. Overall, this study provides valuable insights into the synthesis and characterization of 3% Al-doped ZnO nanoparticles, emphasizing the significant influence of calcination temperature on their structural, morphological, and optical properties, which can be tailored for enhanced photovoltaic applications.