Tube length optimization of titania nanotube array for efficient photoelectrochemical water splitting

Kazuki Inoue; Atsunori Matsuda; Go Kawamura

doi:10.1038/s41598-022-27278-5

Tube length optimization of titania nanotube array for efficient photoelectrochemical water splitting

Sci Rep. 2023 Jan 3;13(1):103. doi: 10.1038/s41598-022-27278-5.

Authors

Kazuki Inoue¹, Atsunori Matsuda¹, Go Kawamura²

Affiliations

¹ Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi, 441-8580, Japan.
² Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi, 441-8580, Japan. kawamura.go.km@tut.jp.

Abstract

Anodic TiO₂ nanotube arrays (TNTAs) have attracted much attention due to their excellent photoelectrochemical (PEC) properties. In this work, the tube length of TNTAs was optimized for efficient PEC water splitting under two different conditions, in which very few or a massive amount of gas bubbles were generated on the electrodes. As a result, relatively longer TNTAs were found to be preferable for higher PEC performance when a larger number of bubbles were generated. This suggests that the mass transport in the electrolyte is assisted by the generated bubbles, so that the electrode surfaces are more easily exposed to the fresh electrolyte, leading to the higher PEC performance.