Self-driven flow in surface grooves fabricated by femtosecond laser

• We make aluminum surface superhydrophilic by using femtosecond laser.
• We can change the dynamic properties of the water in the surface grooves.
• Increasing laser pulse overlap will increase the surface unevenness.
• Increasing laser pulse overlap will change the surface chemical composition.
• The self-driven effect may find a wide range of applications in microfluidics.

The self-driven flow in microfluidic devices has attracted much attention due to its efficient, fast and convenient properties. We investigated the effect of femtosecond laser pulse overlap on the liquid flow characters in surface grooves both in experimental evidence and theoretical analysis. With the increase of the femtosecond laser pulse overlap, the speed of water flowing in grooves is increased. Both the surface granular protrusions microstructures and the surface chemical composition can influence the liquid dynamics in grooves. Femtosecond laser may have potential applications in self-driven microfluidic devices.