This paper reports the performance of alizarin based SnO2 dye-sensitized solar cells. A novel template assisted method has been applied for the preparation of tin oxide nanoparticles. For the first time, onion (Allium cepa) was used as a template for the synthesis of tin oxide nanostructures at different pH values. Tin oxide nanostructures were used for the photoanode preparation. A sandwich cell was prepared by using the dye soaked SnO2 film as a photoanode and platinum as a counter electrode. The structural, morphological and optical properties of the nanoparticles were studied using powder X-ray diffraction (XRD), Scanning Electron microscope (SEM), Photoluminescence (PL), Attenuated Total Reflectance (ATR) spectra and UV–visible spectroscopic techniques. Current–voltage (I–V) characteristics have been measured using electrochemical workstation under the presence of solar illumination. Characteristic parameters of the fabricated cell were determined on the basis of the measured I–V curves.