Synthesis and characterization of mesoporous silica/cerium titanate nanocomposite materials for application in solar cells

Pure CeTiO۴, mesoporous SiO۲, and SiO۲:CeTiO۴ (۲۰-۸۰ wt.%) nanocomposite materials were synthesized and their morphology, structural and optical properties were investigated. FESEM images of amorphous revealed that SiO۲ particles had a spherical morphology ranging in size from ۲۵ to ۵۰ nm with the tendency to agglomerate. CeTiO۴ particles were around ۵۰ nm in size which formed a mixture of irregular, spherical, and plate-like morphologies with different appearances and larger diameters. The UV-Vis DRS spectra displayed that the SiO۲ had the maximum light reflectance intensity whereas CeTiO۴ possessed the lowest intensity. Besides, by decreasing the SiO۲ quantity in the SiO۲:CeTiO۴ nanocomposites, a reduction in reflection was noticed. Also, band gap (Eg) values of amorphous SiO۲ and CeTiO۴ were ۳.۴۰ and ۲.۳۰ eV, respectively, and adding more SiO۲ with higher band gap energy to composites raised the band gap energies to ۲.۳۵ and ۲.۵۰ eV for (۲۰:۸۰ and ۸۰:۲۰ wt.%) SiO۲: CeTiO۴ nanocomposites. Due to the proper transportation and separation of charges, substances with lower Eg energies were believed to exhibit superior visible light activity and outstanding efficiency when applied in solar cells. Hence, a small amount of SiO۲ in nanocomposites would be desirable to reach a suitable band gap. Finally, it could be said that the SiO۲:CeTiO۴ (۲۰-۸۰ wt.%) nanocomposites with desirable characteristics could be very promising materials for application in solar cells and photovoltaic devices.

کلیدواژه ها:

Mesoporous SiO۲ ، CeTiO۴ ، nanocomposite ، Synthesis ، FESEM images ، XRD patterns