Enhanced Efficiency of Dye-Sensitized Solar Cells Using Anodic Titanium Oxide Nanotube Arrays

Abstract

This paper concerns the microstructure of the anodic titanium oxide ͑ATO, TiO 2 ͒ nanotube ͑NT͒ and its use for the dye-sensitized solar cell ͑DSSC͒ device. The ATO length was controlled by various electrolytes and anodic time at various constant applied voltages. The lengths of the NTs at 0.3-0.5 and 0.9-22 m were controlled by 0.5 vol % HF and 0.58 wt % KF aqueous solutions for varied periods of anodization ͑1-24 h͒. The 0.5 wt % NH 4 F electrolyte in ethylene glycol can produce 4-41 m for varied periods of anodization ͑0.5-8 h͒. ATO made of 0.3 ͑0.5 vol % HF͒, 12 ͑0.5 wt % KF͒, and 18 m ͑0.5 wt % NH 4 F͒ was used for the DSSC anode; the best cell performance attained 0.13, 3.76, and 6.18%. The DSSC made of 18 m ATO has a short-circuit current density ͑J sc ͒ of 13.45 mA/cm 2 , a fill factor of 0.64, an open voltage ͑V oc ͒ of 0.72 V, and a photocurrent efficiency of 6.18% under an air mass 1.5 illumination test.

Alumina Template Assistance in Titania Nanotubes Dye-Sensitized Solar Cell ( NT-DSSC) Device Fabrication

“…We have also made TiO 2 NT film [32][33][34][35][36] and used it for DSSC device fabrication, allowing the photovoltaic power conversion efficiency to reach η ∼7% [14,37]. In this paper, we have combined our previous Al 2 O 3 template, TiO 2 NT, and DSSC fabrication technologies to achieve an Al 2 O 3 /TiO 2 NT-DSSC device.…”

Electrochemical impedance spectroscopy to study photo - induced effects on self-organized TiO2 nanotube arrays

“…Considerable efforts have been done during the last years to elaborate nanostructured TiO 2 layers which combine the interesting semiconducting and photoelectrochemical properties of titanium oxide with a huge internal surface area and improved charge transport properties [1][2][3][4]. Among the nanosized TiO 2 films, titania nanotubes have raised considerable interest, specially those made by anodization of titanium in fluoride-based baths [4][5][6][7][8][9].…”

Fabrication and Characterization of Highly-Ordered Valve-Metal Oxide Nanotubes and Their Derivative Nanostructures

“…By using KF containing electrolyte anodization (0.58 wt.% KF + 13.8 wt.% NaHSO 4 · 2H 2 O + 5.9 wt.% C 6 H 5 Na 3 O 7 · 2H 2 O, pH = 4.7, 25 V, 1 h), pores with 0.8 m thickness were obtained, as shown in Figure 27(c), and pores with 5-50 m thickness were obtained in NH 4 F containing electrolyte (0.5 wt.% NH 4 F + 2 vol.%, H 2 O + C 2 H 4 (OH) 2 , pH = 6.8, 60 V, 0.5-8 h), as shown in Figure 27(d). Figure 28 shows TEM images of TiO 2 NTs made by anodization in solutions containing (a) HF, (b) KF, and (c) NH 4 F. 170 In the first stage of the anodization, the degree of ordering on the surface of ATO is low, since the surface of the initial material is relatively rough on the micrometer scale. As a result, holes develop randomly.…”