Nanosecond Laser Fabrication of Superhydrophobic and Superoleophilic Surface on Copper Foam

A superhydrophobic and superoleophilic surface-based copper foam was fabricated using one-step nanosecond laser patterning and the influence of laser processing parameters on the wettability of its surface was studied. To investigate the surface morphology, elements, and wetting properties, scanning electron microscopy, energy dispersive X-ray spectroscopy, and contact angle measurement were performed. The results show that as the laser scanning speed, power, and scanning spacing increase, the rough structure of copper foam surface changes considerably. In addition, the chemical composition of the laser-ablated surface changes. Superhydrophobicity and superoleophilicity are caused by the rough structures and changes in chemical composition. The superhydrophobic and superoleophilic surface's maximum water contact angle in the air is 157.4 degrees, while the oil contact angle is 0 degrees. The ablated surface can successfully separate oil from water, providing oil-water separation and oil recycling practice guidelines.