Incorporation of Ag Nanoparticles on Titania Nanotubes using Pulse Current Deposition for Dye-Sensitized Solar Cells Application

Abstract

Dye-sensitized solar cells (DSSCs) have gained a lot of interest, because of their high photoconversion efficiency and less cost. In this work DSSCs were fabricated with Silver (Ag) nanoparticles (NPs) decorated titanium dioxide nanotubes (TiNTs). TiNTs with two type morphologies, open and grassy were synthesized by a two-step anodization method by utilizing of Ti sheet and then depositing Ag NPs on TiNTs by pulse current deposition (PCD) method. Pulse current deposition (PCD) manufactures homogeneous nanoparticles with adjustable size distribution by changing pulse parameters. Moreover, PCD approach has never been employed for decorating Ag nanoparticles on TiNTs by tuning pulse current as photoanode in DSSCs. This research work is the first attempt to apply PCD method by tuning pulse current for increasing plasmon effect in DSSCs. Ti was first anodized in two steps at 50 V for 2 h at 20 °C in a two-electrode cell geometry for the synthesis of TiNTs with open and grassy morphologies and then deposition of Ag NPs of different sizes on TiNTs was done using PCD at pulse currents of 10, 15 and 25 mA/cm2 . Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), X-Ray Diffraction (XRD), Raman, and Photoluminescence spectroscopy (PL) were utilized to study the morphology, elemental composition, structure, and optical characteristics of the prepared samples, respecvtively. The samples were then utilized as a photoanode in a back-sideilluminated dye-sensitized solar cell. The effect of Ag particle size and deposition on the TiNTs as photoanode in DSSCs was studied. The results showed that Ag NPs decorated onto TiNTs with open tube tops, at a pulse current of 15 mA/cm2 exhibited the maximum photoconversion efficiency (η) of 4.46% and a short-circuit current density of 9.66 mA/cm2 . These results suggest that TiNTs with open tube tops decorated with optimum amount of Ag NPs as a photoanode increases the efficiency of DSSCs. This method can be utilized to create various metal-loaded nanotube array materials for energy harvesting applications