Synthesis and characterization of ZnO nanoparticles and their application in dye-sensitized solar cells

Simple and easy synthesis of ZnO nanoparticles is done using Zinc metal dust and double distilled water. ZnO nano-powder is synthesized by using two methods: reflux (ZnO) and hydrothermal methods (ZnO-24 h. and ZnO-48 h.) using Zinc metal dust as a precursor. Photoanode plays an important role in dye-sensitized solar cells, a compact layer is included via the SILAR method to reduce the recombination. The hydrothermal synthesis is carried out at two different temperatures. Results show that ZnO powder has a wurtzite crystalline structure with a band gap of 3.2 eV. Here these powders are further used to fabricate Dye-Sensitized Solar cells. From J-V characteristics the short circuit current for ZnO was 1.88 mA cm⁻², Voltage was observed to be 0.54 V, fill factor was observed to be 0.48, and Efficiency was observed to be 0.5%. The various other parameters such as chronoamperometry, chronopotentiometry, and Electrochemical Impedance spectroscopy supporting the J-V characteristics were also studied. The external quantum efficiency very well supports the optical absorption spectra of the N3 dye.