Fabrication of oil-water separation stainless steel mesh via direct laser interference lithography, candle soot deposition, and thermal treatment

In this work, the authors propose a method to obtain micro- and nano-structures on the stainless steel mesh (SSM), which showed the potential application for the treatment of water pollution based on its hydrophobicity and oleophilicity. The textured surfaces with the micrometer scale pore array patterns on the SSM are formed by three-beam laser interference lithography. And the nanostructures, such as nanorods, nanowires, and nanoflakes, are obtained on the surfaces of the SSMs after laser irradiation by heating for 70 min at approximately 600 degrees C under ambient conditions. The results showed that the nano-structures can be easier to grow on the rough surface than the smooth ones. In addition, these nanostructures are also grown on the surfaces of the laser irradiated SSM with the candle soot (LISSM@C). Raman spectrum proves that the nanostructures are alpha-Fe2O3 and alpha-Fe2O3/reduced graphene oxide (rGO). The measurement of the contact angle indicates that the oil-water separation can be realized on the LISSM@C after the thermal treatment.