Ultrasonic Dispersion of Pyrolytic Carbon: Synthesis, Characterization, and Photoluminescence Properties of Stable Colloidal Solutions
Source abstract
Abstract
Contemporary science is seeking simple and scalable methods of producing stable colloidal solutions of carbon nanomaterials that have favorable optical properties. Pyrolytic carbon (PyC), a by-product of methane pyrolysis, is a promising sustainable material. This study developed a method of obtaining stable PyC colloids using ultrasonic homogenization and investigated the effects of solvent polarity on dispersion, stability, and photoluminescence. Mechanically fragmented PyC was ultrasonically treated in ethanol, acetonitrile, and cyclohexane. Characterization using dynamic light scattering, UV-Vis spectroscopy, photoluminescence, Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and electron microscopy revealed that solvent polarity significantly influenced fragmentation and colloid stability. Polar solvents, especially ethanol, promoted better dispersion of aggregates, whereas nonpolar cyclohexane produced smaller, yet unstable aggregates. Raman and FT-IR analyses confirmed graphitic domains and oxygen-containing surface groups, which are critical to colloidal stability. UV-Vis spectra displayed solvent-dependent shifts in absorption edges, while photoluminescence spectra showed blue emission centered at ~490 nm, which is linked to surface states. Electron microscopy verified the presence of spherical nanoparticles with a diameter of ~20 nm and high carbon purity after sedimentation. These results demonstrate that ultrasonic treatment combined with solvent selection provides a straightforward route to photoluminescent PyC colloids with potential applications in sensors, bioimaging, and optoelectronics.
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Research context
OpenAlex topics: Carbon and Quantum Dots Applications · Carbon Nanotubes in Composites · Graphene and Nanomaterials Applications
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Faculty of Materials Engineering and Physics, Cracow University of Technology, Podchorążych 1, 30-084 Cracow, Poland
Oil and Gas Institute-National Research Institute, Lubicz 25A, 31-503 Cracow, Poland
Faculty of Chemical Engineering and Technology, Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland
Faculty of Mechanical Engineering, Silesian University of Technology, Konarskiego 18A, 44-100 Gliwice, Poland
Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Cracow, Poland
Funding
National Science Centre, Poland
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