On the conversion of point-to-linear hierarchical micro/nano-structures on the glassy carbon surface by nanosecond pulsed laser irradiation

Fabrication of microstructures on the glassy carbon (GC) surface is crucial for its functional applications. However, due to its intrinsic mechanical, physical, and chemical properties, it is still challenging to fabricate hierarchical micro/nano-structures on the GC surface. In this study, by tuning the interval between adjacent points as well as the irradiation time, the conversion from the point to linear hierarchical micro/nano-structures was successfully achieved on the GC surface by nanosecond pulsed laser irradiation. The detailed conversion process and mechanism were explored and discussed. On this basis, the linear hierarchical micro/nano-structures were fabricated by direct line scanning, and the internal nanostructures were always parallel to the laser scanning direction. By repeated line scanning with relatively low laser fluence, the method of direct line scanning was further improved, and well-defined and uniform hierarchical micro/nano-structures were fabricated.