MDPI - Publisher of Open Access Journals

8 pages, 322 KiB

Open AccessCommunication

Laser Intensity Effect on Polyyne Synthesis in Liquid Hydrocarbons

by Vitali V. Kononenko, Natalia R. Arutyunyan, Kuralay K. Ashikkalieva, Evgeny V. Zavedeev, Taras V. Kononenko, Ekatherina V. Akhlyustina and Vitaly I. Konov

Photonics 2023, 10(10), 1100; https://doi.org/10.3390/photonics10101100 - 29 Sep 2023

Cited by 4 | Viewed by 1238

Abstract

Laser synthesis of polyyne molecules C

_{2 n}

_{2}

Laser synthesis of polyyne molecules C

_{2 n}

_{2}

(n > 2) in liquid hydrocarbons is a complex process in which intense pulsed radiation decomposes the initial carbon-containing substance (the hydrocarbon solvent itself or the solid carbon particles in a suspension). Notwithstanding the fact that the mechanism of pulsed laser ablation in liquids (PLAL) is widely accepted, the effect of the laser parameters on laser-driven polyyne formation is still not understood in detail. Here, we report a study of the polyyne yield as a function of the laser field intensity and exposure dose. Several carbon-containing liquids, including pure n-hexane, pure ethanol, and graphite powder suspended in ethanol, were treated with tightly focused picosecond IR radiation (wavelength of 1064 nm, pulse duration of 10 ps). The synthesis rate was characterized by UV-vis optical absorption spectroscopy. The yields of the polyynes were found to vary in exact accordance with the value of the absorbed laser energy, following specific nonlinear or linear laws. The influence of the laser intensity on the partial concentration of polyynes in the solution was analyzed. Full article

(This article belongs to the Section Optical Interaction Science)

► Show Figures

Figure 1

14 pages, 2984 KiB

Open AccessArticle

Femtosecond Laser Ablation of a Bulk Graphite Target in Water for Polyyne and Nanomaterial Synthesis

by Nikolaos G. Semaltianos, Ona Balachninaitė, Remigijus Juškėnas, Audrius Drabavicius, Gediminas Niaura and Euan Hendry

Appl. Sci. 2023, 13(18), 10388; https://doi.org/10.3390/app131810388 - 17 Sep 2023

Cited by 1 | Viewed by 2300

Abstract

Laser ablation of a bulk graphite target in water using femtosecond laser pulses (pulse width ≤ 190 fs) was performed to investigate the synthesis of polyynes and carbon-based nanomaterials and compare them with the well-studied cases of longer pulse (picosecond or nanosecond) ablations. The laser ablation products were characterized using UV-vis absorption spectroscopy, Raman spectroscopy, X-ray diffraction, and transmission electron microscopy, whereas the induced plasma plumes were characterized using laser-induced breakdown spectroscopy. Carbon-based nanomaterials and short-chain polyynes (C₆H₂ and C₈H₂) are formed in the solutions as proven by their characteristic absorption band at ~262 nm and peaks in the region of 190–240 nm as well as at around 2100 cm⁻¹ in the Raman spectra, respectively. Polyynes (C₈H₂) are present in the solutions that are produced under an ablation that is carried out in two intervals with a short pause between them, which is contrary to a continuous ablation that is performed for the same total time duration. The ablation products have a hexagonal graphite crystal structure. The carbon-based nanomaterials consist of large non-spherical and small spherical nanoparticles as well as sheet-like structures. The results of the study were compared with previous studies and discussed based on those studies. Full article

(This article belongs to the Special Issue Applied Laser Processing, Manufacturing, and Materials Science)

► Show Figures

Figure 1

Search Results (2)

Further Information

Guidelines

MDPI Initiatives

Follow MDPI

Saved Queries

Search Filter Reset All

Years

Feature Papers

Subjects

Journals

Article Types

Countries / Regions

Search Results (2)

Further Information

Guidelines

MDPI Initiatives

Follow MDPI