Long K‐Doped Titania and Titanate Nanowires on Ti Foil and FTO/Quartz Substrates for Solar‐Cell Applications

Abstract

Potassium‐doped titania and titanate nanowires are fabricated by moisture‐assisted direct oxidation of titanium. The influence of the fabrication conditions on nanowire structure and morphology is investigated. It is shown that the presence of potassium is essential for nanowire formation, while the nanowire structure and morphology are strongly dependent on the fabrication temperature. The longest nanowires (ca. 10 μm) are obtained at 650 °C. At this substrate temperature, nanowires could be produced over a large substrate area both by oxidation of the Ti foil as well as by depositing a Ti film on the substrate (quartz or fluorine‐doped tin oxide (FTO)/quartz). Photovoltaic cells based on these nanowires are fabricated. The cell performance is dependent on the nanowire fabrication temperature and the substrate used, as well as on the annealing environment. Short‐circuit current densities of Isc = 3.05 mA cm–2 and Isc = 4.97 mA cm–2 could be obtained for Ti foil and FTO/quartz substrates, respectively, while the corresponding power‐conversion efficiencies are η = 0.93 % and η = 1.88 % (under AM 1.5 illumination, 100 mW cm–2; AM: air mass).

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

“…To improve charge-collection efficiency by promoting faster electron transport and slower charge recombination, several different methods have been established using TiO 2 films constructed of oriented onedimensional (1D) nanostructures. For example, the best cell performance of DSSCs based on 1D TiO 2 nanowires (NWs) has reached η = 5.0% under front-side illumination [7,8]. Also, 1D TiO 2 nanotubes (NTs) have been synthesized using sol-gel [9] and potentiostatic anodization [10] that allow it to outperform the conventional NP-DSSCs.…”

Organic Nanoclusters on Inorganic Nanostructures for Tailoring the Emission Properties of Organic Materials

“…NiO nanostructured films were also prepared by a hydrothermal method from solutions of nickel nitrate hydrate and hexamethylene tetramine. TiO x nanowires were prepared by oxidation of Ti foil in the presence of water vapor and KF [32] for 2 hours in a tube furnace at a temperature of 650 -C and a pressure of 70-80 Torr. All of the chemicals used for inorganic nanostructure synthesis were obtained from Aldrich.…”

Synthesis of TiO2 hollow spheres with tunable pore structure and enhanced photocatalytic activity

“…On the other hand, it is well known that morphology and microstructures are very important to the photocatalytic activity of titania. Therefore, there are many studies focused on the new structures of titania, such as nanorods [14,15], nanowires [16,17], and nanotubes [18,19], etc.…”