Structural, morphological and optical properties of SnO2 nanoparticles obtained by a proteic sol-gel method and their application in dye-sensitized solar cells

Abstract

Tin dioxide nanoparticles were synthesized by the proteic sol–gel method. Tin chloride (SnCl4·5H2O) was used as source of Sn4+ and commercial gelatin as organic precursor. Several calcination temperatures were employed. Thermogravimetric analysis and differential scanning calorimetry were performed to investigate the thermal behavior of the precursor powders as well as to select the appropriate calcination temperatures for oxide formation. Structural, morphological, and optical properties of the synthesized materials were studied by X-ray diffraction, transmission electron microscopy, Fourier transformed infrared spectroscopy, and ultraviolet–visible spectroscopy. The results confirmed the formation of spherical nanoparticles of rutile SnO2 with an optical absorption band in the ultraviolet region near the visible light range. Thermally treated samples showed improved crystallinity and superior transparency to visible light. These SnO2 nanoparticles were successfully employed as photoanode material in dyesensitized solar cells. The performance of the cells was evaluated by measuring J × V curves in a solar simulator and was found to be in line with results in the literature.