Fabrication of super hydrophilic surface on alumina ceramic by ultrafast laser microprocessing

Abstract In this research, super hydrophilic surface on the alumina ceramic substrate is fabricated by ultrafast laser microprocessing. The laser textured surface developed by femtosecond laser in the air atmosphere is able to maintain the super hydrophilic property for 36 h and still remains hydrophilic with the contact angle of 57.9°after 240 h. Surface morphology and chemical composition of the laser textured surface are characterized by scanning electron microscope (SEM), 3D laser scanning confocal microscope (LSCM) and X-ray photoelectron spectroscope (XPS). Results show that femtosecond laser can provide larger surface roughness in contrast with picosecond laser. Laser microprocessing can also increase the content of oxygen element and polar functional groups on the surface of the alumina ceramic substrates. Furthermore, the mechanism of the hydrophilic behavior of droplets on the laser textured surface is discussed in details and it is noted that surface morphology plays a leading role in amplifying the inherent wettability. We envision that the laser microprocessing provides a facile and effective route to develop long-term super hydrophilic surface on alumina ceramic materials.