A short-range ordered-disordered transition of a NiOOH/Ni(OH)2 pair induces switchable wettability.
By virtue of its amorphous structure with a short-range order feature, the inorganic nanoporous nickel oxyhydroxide (NiOOH) can reversibly and rapidly switch wettability by alternate treatments of environmental chamber (superhydrophobic) and UV/ozone (superhydrophilic). The switchable mechanism of the NiOOH/Ni(OH)2 pair arising from its exceptional intrinsic short-range order-disorder transition together with chemical composition change is highlighted for the first time, which significantly differs from the current stimuli-responsive materials. This distinct multifunctional thin film not only possesses reversible wettability but also is optically patternable/repairable and electrically conductive, which could be applicable in the manufacturing of various micro- and nanostructures. We demonstrate this potential in the rewritable two-dimensional (2D) microfluidic channels and wetting-contrast enhanced selective electroplating.
Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Rd, Hong Kong. hpfeng@hku.hk.
Ya-Huei
YH
Chang
Nga Yu
NY
Hau
Chang
C
Liu
Yu-Ting
YT
Huang
Chien-Cheng
CC
Li
Kaimin
K
Shih
Shien-Ping
SP
Feng