Laser Ablated Carbon Nanodots for Light Emission

Abstract

The synthesis of fluorescent carbon dots-like nanostructures (CNDs) obtained through the laser ablation of a carbon solid target in liquid environment is reported. The ablation process was induced in acetone with laser pulses of 1064, 532, and 355 nm under different irradiation times. Close-spherical amorphous CNDs with sizes between 5 and 20 nm, whose abundance strongly depends on the ablation parameters were investigated using electron microscopy and was confirmed using absorption and emission spectroscopies. The π- π* electronic transition at 3.76 eV dominates the absorption for all the CNDs species synthesized under different irradiation conditions. The light emission is most efficient due to excitation at 3.54 eV with the photoluminescence intensity centered at 3.23 eV. The light emission from the CNDs is most efficient due to ablation at 355 nm. The emission wavelength of the CNDs can be tuned from the near-UV to the green wavelength region by controlling the ablation time and modifying the ablation and excitation laser wavelength.

Carbon Nanodots: A Review—From the Current Understanding of the Fundamental Photophysics to the Full Control of the Optical Response

“…In Ref. [60], the authors demonstrate that ablating graphite with a wavelength in the UV-range (355 nm) produces 5 nm-sized crystalline CDs without the formation of any aggregates, whereas the use of a beam at 532 nm or 1064 nm produces plenty of carbon aggregates. In addition, in this case, no post-synthesis functionalization is needed to obtain highly fluorescent CDs.…”

Optical and dielectric properties of PMMA (poly(methyl methacrylate))/carbon dots composites

“…Up to now, several approaches have been developed for the synthesis of C‐dots, including chemical ablation , electrochemical carbonization , laser ablation , microwave irradiation and hydrothermal/solvothermal treatment . In this work, the nanoparticle synthesis has been performed by thermal decomposition of carbon precursors in hot coordinating solvents.…”

Carbon-based quantum particles: an electroanalytical and biomedical perspective

“…The laser ablation of a solid carbon material in liquid environment with laser pulses of 1064, 532 and 355 nm under different irradiation times was lately investigated. 34 Wide CQDs size distribution was observed for the 1064 nm laser due to the deeper penetration of the laser light into the dielectric during the ablation process, being thus less adapted for the formation of size controlled CQDs.…”

“…Independent of the carbon nanostructure aimed at, the synthetic approaches are generally classified into two main categories: top-down and bottom up. The top-down methods are based on breaking down larger carbon structures such as graphite powder, carbon rods, carbon nanotubes, carbon black and even candle soot, 33 by methods such as laser ablation, 34 hydrothermal, 35,36 electrochemical oxidation, 37,38 or arc discharge. 39 The advantage of the top-down approaches for the preparation of CQDs is that abundant raw materials can be used, allowing large-scale production and simple operation.…”