Mesoporous films prepared from synthesized TiO2 nanoparticles and their application in dye-sensitized solar cells (DSSCs)

Abstract

In this paper, we propose a novel method for preparation of high surface area titania nanoparticles, and investigate their photovoltaic performance in dye sensitized solar cells (DSSCs). The precursor compound titanium(IV)-isopropoxide is hydrolyzed in the presence of nonionic surfactant (Triton X100) and ethylenediaminetetraacetic acid sodium salt (EDTA-Na2) and thermally transformed into gel. The gel is autoclaved, resulting in submicronic micelles which are further processed into mesoporous films. The films are deposited from paste, composed of ultrasonically broken micelles and the organic ingredients. The crack-free film structures, composed of sub–25nm pure anatase particles are observed using the appropriate instrumental techniques: scanning electron microscopy (SEM), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffractometry (XRD), UV-VIS-NIR spectroscopy. The large surface area of 158m2g−1 and mesoporosity are confirmed using the data obtained from the nitrogen adsorption-desorption isotherm. The photovoltaic performance of the operating N719-sensitized solar devices are tested using electrochemical impedance spectroscopy (EIS), open-circuit voltage decay (OCVD) and by recording current density-voltage (J-V) curves. The cell exhibits promising photocurrent density up to 11.7mAcm−2, and the photo-to-electric power efficiency of 5.22%, for cell area of 0.24cm2, under 100mWcm−2 halogen light source.