On-demand oil-water separation via low-voltage wettability switching of core-shell structures on copper substrates

• DOI: 10.1016/j.apsusc.2018.02.238
• Publication Date: 2018-02-27T23:10:19Z
• Authors: Chun Haow Kung; Beniamin Zahiri; Pradeep Kumar Sow; Walter Mérida
• Keywords: Superhydrophilicity; Oil droplet

Abstract A copper mesh with dendritic copper-oxide core-shell structure is prepared using an additive-free electrochemical deposition strategy for on-demand oil-water separation. Electrochemical manipulation of the oxidation state of the copper oxide shell phase results in opposite affinities towards water and oil. The copper mesh can be tuned to manifest both superhydrophobic and superoleophilic properties to enable oil-removal. Conversely, switching to superhydrophilic and underwater superoleophobic allows water-removal. These changes correspond to the application of small reduction voltages (