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A double pulse LII experiment on carbon nanoparticles: insight into optical properties
Francesca Migliorini1, Silvia Belmuso2, D Ciniglia1
1CNR-ICMATE, Institute of Condensed Matter Chemistry and Technologies for Energy, via Cozzi 53, 20125 Milano, Italy. silvana.deiuliis@cnr.it.
Physical Chemistry Chemical Physics : PCCP
|August 10, 2022
Summary
This study investigated carbon nanoparticles using a modified Laser-Induced Incandescence (LII) method. Pre-irradiation with lasers significantly altered nanoparticle properties, especially for younger particles.
Area of Science:
- * Nanoparticle characterization and laser-matter interactions.
- * Combustion diagnostics and aerosol science.
Background:
- * Carbon nanoparticles are crucial in combustion processes and material science.
- * Laser-Induced Incandescence (LII) is a common technique for nanoparticle property measurement.
Purpose of the Study:
- * To investigate the effects of pre-laser irradiation on carbon nanoparticle properties.
- * To compare the influence of irradiation on young versus mature carbon nanoparticles.
- * To understand the underlying physical phenomena related to laser-irradiated nanoparticles.
Main Methods:
- * Employed a double-pulse experiment, a modified Laser-Induced Incandescence (LII) approach.
- * Irradiated carbon nanoparticles (from ethylene/air flame) with varying laser fluences prior to LII.
- * Conducted two-color LII measurements on pristine and irradiated nanoparticles.
- * Analyzed changes in incandescence signal, temperature, and concentration.
Main Results:
- * Observed a significant increase in apparent particle volume fraction with increasing laser fluence.
- * Noted a noticeable increase in the LII signal intensity correlated with pre-irradiation fluence.
- * Found these effects to be more pronounced in younger carbon nanoparticles than mature ones.
Conclusions:
- * Laser pre-irradiation significantly influences measured carbon nanoparticle properties, particularly volume fraction and LII signal.
- * The observed phenomena are more pronounced in younger, potentially less developed, nanoparticles.
- * Electrical properties of carbon nanoparticles may play a role in their response to laser irradiation.
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