High-resolution patterning of graphitic carbon structures in laser carbonization of cellulose nanofiber film

Laser carbonization is a facile method for patterning graphitic carbon structures. Generally, patterning graphitic carbon structures with narrow line widths is difficult in laser carbonization due to the thermal effects generated during the modification process. In this study, we demonstrated that graphitic carbon structures with narrow line widths (approximately 4 µm) can be directly patterned in laser carbonization of Cellulose Nanofiber (CNF). Our technique enabled low-power patterning, presumably suppressed thermal effects during modification, and resulted in structures with narrow line widths. The line widths increased linearly with laser power and were readily controllable. We applied the patterned structures to Fresnel Zone Plates (FZP) and demonstrated that the FZP can focus laser light in the visible wavelength. The proposed method is facile and enables high-resolution patterning of graphitic carbon structures.