One-Dimensional ZnO Nanostructures by Wet-Chemistry Technique for Dye Sensitized Solar Cell Application

In the current work, ZnO nanoflowers have been synthesized via sol-gel technique using a mixture of zinc-nitratetetrahydrate, ammonia and polyethylene glycol (PEG). Variation in PEG concentration and ammonia evaporation delay time was performed and the resulting nanoflowers have been investigated using x-ray diffraction (XRD) and scanning electronmicroscope (SEM). To explore the potential of the resulting ZnO nanorods, a prototype of dye sensitized solar cell (DSSC) has been fabricated. For this purpose, the nanorods were grown directly on conducting ITO substrates by nanoseeding technique. With a variation in nano seeding time for 2, 4 and 6 days, followed by hydrothermal process at 80°C for 20 hours, ZnO nanorods with average diameter of 82, 332 and 1385 nm have been synthesized. The performance test showed the resulting open circuit voltage (V_oc) was increased from 398 to 486 mV when the diameter of ZnO nanorods increased from 82 to 332 nm. However, the V_oc decreased slightly to 456 mV when the nanorods further increased to 1385nm. The phenomenon is related to the interaction between the semiconductor oxide and the Ruthenium complex organic dye.