Enhancing the Contact Area of Ti Wire as Photoanode Substrate of Flexible Fiber-Type Dye-Sensitized Solar Cells Using the TiO2 Nanotube Growth and Removal Technique

Abstract

The fiber-type dye-sensitized solar cell (FDSSC) with flexible and dim-light workable features is one of the promising energy generation devices for soft electronics. A novel TiO2 nanotube (TNT) growth and removal technique is proposed in this study to enhance the contact area of the Ti wire substrate using anodization and ultrasonication processes. Smaller and denser imprints of TNT on the surface of Ti wire are obtained when a smaller voltage was applied for anodization. The thickness of the TiO2 nanoparticle layer coated on the Ti wire is also optimized by varying the dip-coating layers. With the smallest diameter and densest distribution of TNT imprints on the Ti wire, the FDSSC with the TiO2/TNT-printed Ti wire photoanode, prepared using 30 V as the anodization voltage, shows the highest photon-to-electricity efficiency of 2.37% as a result of the rough surface of Ti wire substrate, which provides more contact, as well as the suitable thickness of the TiO2 nanoparticle layer, which promotes charge generation and transportation. The smallest charge-transfer resistance and the highest electron collection efficiency are also obtained in this case, as examined using the electrochemical impedance spectroscopy and intensity modulated photocurrent spectroscopy/intensity modulated photovoltage spectroscopy. This facile TNT growth and removal technique is expected to be able to be applied to other fields for enhancing the contact area of the titanium substrate and promoting the generation of electrochemical reactions.

Enhanced Mechanical and Thermal Properties of Stereolithography 3D Printed Structures by the Effects of Incorporated Controllably Annealed Anatase TiO2 Nanoparticles

“…Conversely, the eco-friendly, high refractive index, optical transparency, low toxicity, low-cost, and high mechanical behaviors of titanium dioxide nanoparticles (TNPs) are thought to make it one of the greatest effective semiconductor photocatalysts for conservational applications. In addition, the low energy bandgap of about 3.2 eV of TNPs stimulates excellent photocatalysis reactions under UV light irradiation [46][47][48][49][50]. Nowadays, many nanostructured TiO 2 materials, such as nanoparticles, nanotubes, and nanowires, are synthesized using many proposed routes such as sol-gel, hydrothermal and anodic oxidation methods [51][52][53][54][55][56][57][58].…”

TiO2 nanotubes for dye‐sensitized solar cells—A review

“…Decorating the TNTs with nanoparticles (NPs) is a common modification method to increase the active area of TNTs to improve the PCE of TNT‐based DSSCs, 81 which is due to the enhanced dye absorption ability and promoted charge transfer 67,82,83 . TiO 2 NPs are the most used NPs to enhance the PCE in DSSCs 70,81,84‐87 .…”

Sol-Gel Processed TiO2 Nanotube Photoelectrodes for Dye-Sensitized Solar Cells with Enhanced Photovoltaic Performance

“…To the best of our knowledge, the most of publications which deal with TiO 2 NTs-based photoelectrodes report the fabrication of nanotubes by anodization of the Ti foils that is rather a complicated fabrication method [20,[23][24][25]. Moreover, the reported efficiencies of the DSCs fabricated with TiO 2 NTs produced by anodization do not exceed those for TiO 2 NPs-based devices due to lower surface area of the TiO 2 NTs which limits the amount of the absorbed dye molecules and decreases light-harvesting ability [20,26].…”