Fish-scale nickel mesh with switchable wettability for efficient oil/water separation

In the daily life of human beings, sewage discharge and oil spill accidents occur from time to time. New types of controllable oil/water separation interface materials have received more attention. In this study, we proposed a simple and environmentally friendly method to prepare a Nickel filter with switchable wettability . The final product is prepared by high temperature calcination and soaked with stearic acid ethanol solution. The prepared filter screen has selective separation performance for oil/water mixture with switchable surface wettability between superhydrophobic and superhydrophilic. The separation efficiency is higher than 99.50%, and the flux rate is as high as 46.25 L m −2 s −1 for water-removing process and 40.22 L m −2 s −1 for oil-removing process. The wettability conversion of the membrane can be achieved through heating treatment and soaking treatment, and it still has good oil/water separation performance. After 20 times of cycles, the separation efficiency remains unchanged, and the flux remain above 40.06 L m −2 s −1 for oil removal and 36.81 L m −2 s −1 for water removal process. The results show that the prepared nickel filter screen has good practical application prospects such as water reclamation and oil spill treatment.