Reversible Photocontrol of Wood-Surface Wettability Between Superhydrophilicity and Superhydrophobicity Based on a TiO₂ Film

Abstract

The reversible photocontrol of wood-surface wettability between superhydrophilicity and superhydrophobicity based on a TiO₂ film modified with octadecyl trichlorosilane (OTS) was achieved via a facile hydrothermal method at low temperature. Under UV illumination, the wood surface became superhydrophilic with a water contact angle (WCA) of approximately 0°. However, when placed in the dark, a superhydrophobic wood surface with a WCA of approximately 152° was achieved. The mechanism of the reversible photocontrol of wood-surface wettability is discussed in this article. This photocontrolled wood surface may have potential for wood self-cleaning or manipulation in response to indoor humidity.

KEYWORDS:

• TiO₂
• UV-drive
• reversible wettability
• low-temperature hydrothermal method