Initial interpretation of Laser-induced Incandescence (LII) signals from flame-generated TiO2 particles: Towards a quantitative characterization of the flame synthesis processes
Among various optical diagnostics for the characterization of particle formation in flames, laser-induced incandescence (LII), developed for soot particles, is attracting attention for the study of flame synthesis of metal-oxides. Among them, TiO2 nanoparticles are widely used for pigments and photo...
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| Format: | Article |
| Language: | English |
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Elsevier
2023-09-01
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| Series: | Applications in Energy and Combustion Science |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2666352X23000791 |
| _version_ | 1797688906732273664 |
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| author | J. Yi C. Betrancourt N. Darabiha B. Franzelli |
| author_facet | J. Yi C. Betrancourt N. Darabiha B. Franzelli |
| author_sort | J. Yi |
| collection | DOAJ |
| description | Among various optical diagnostics for the characterization of particle formation in flames, laser-induced incandescence (LII), developed for soot particles, is attracting attention for the study of flame synthesis of metal-oxides. Among them, TiO2 nanoparticles are widely used for pigments and photocatalysts. Recent works have shown the feasibility of LII for flame-synthesized TiO2, but extensive research is still needed to quantitatively characterize TiO2 production in flames with LII measurements. In this work, the first attempt towards the characterization of TiO2 synthesis in flames is provided as a normalized volume fraction. To achieve this, TiO2 nanoparticles are generated in a laminar coflow diffusion flame of argon-diluted hydrogen and air with pre-vaporized titanium isopropoxide (TTIP). A 355 nm laser is used to irradiate the flame-generated particles. Spectral, temporal, and spatial measurements are performed at various flame heights. First, laser-induced emission (LIE) at prompt is investigated for different laser fluences to identify the operating conditions that ensure the LII-like nature of the measured signals. The LIE at high fluence presents sharp features that contain information on the atomic composition of the particles and of the vaporized species when compared to reference spectra of carbon black and high-purity TiO2 particles. Then, the LII signal at lower fluence is used to obtain an estimation of the spatial evolution of the normalized volume fraction and of the LII signal decay time. These results are finally used to discuss the major aerosol processes along the flame centerline. |
| first_indexed | 2024-03-12T01:38:20Z |
| format | Article |
| id | doaj.art-92a237e4f70844bab3bcf09b2653df5f |
| institution | Directory Open Access Journal |
| issn | 2666-352X |
| language | English |
| last_indexed | 2024-03-12T01:38:20Z |
| publishDate | 2023-09-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Applications in Energy and Combustion Science |
| spelling | doaj.art-92a237e4f70844bab3bcf09b2653df5f2023-09-11T04:17:41ZengElsevierApplications in Energy and Combustion Science2666-352X2023-09-0115100190Initial interpretation of Laser-induced Incandescence (LII) signals from flame-generated TiO2 particles: Towards a quantitative characterization of the flame synthesis processesJ. Yi0C. Betrancourt1N. Darabiha2B. Franzelli3Laboratoire EM2C, CNRS, CentraleSupélec, Université Paris-Saclay, Gif-sur-Yvette, 91190, FranceLaboratoire EM2C, CNRS, CentraleSupélec, Université Paris-Saclay, Gif-sur-Yvette, 91190, FranceLaboratoire EM2C, CNRS, CentraleSupélec, Université Paris-Saclay, Gif-sur-Yvette, 91190, FranceCorresponding author.; Laboratoire EM2C, CNRS, CentraleSupélec, Université Paris-Saclay, Gif-sur-Yvette, 91190, FranceAmong various optical diagnostics for the characterization of particle formation in flames, laser-induced incandescence (LII), developed for soot particles, is attracting attention for the study of flame synthesis of metal-oxides. Among them, TiO2 nanoparticles are widely used for pigments and photocatalysts. Recent works have shown the feasibility of LII for flame-synthesized TiO2, but extensive research is still needed to quantitatively characterize TiO2 production in flames with LII measurements. In this work, the first attempt towards the characterization of TiO2 synthesis in flames is provided as a normalized volume fraction. To achieve this, TiO2 nanoparticles are generated in a laminar coflow diffusion flame of argon-diluted hydrogen and air with pre-vaporized titanium isopropoxide (TTIP). A 355 nm laser is used to irradiate the flame-generated particles. Spectral, temporal, and spatial measurements are performed at various flame heights. First, laser-induced emission (LIE) at prompt is investigated for different laser fluences to identify the operating conditions that ensure the LII-like nature of the measured signals. The LIE at high fluence presents sharp features that contain information on the atomic composition of the particles and of the vaporized species when compared to reference spectra of carbon black and high-purity TiO2 particles. Then, the LII signal at lower fluence is used to obtain an estimation of the spatial evolution of the normalized volume fraction and of the LII signal decay time. These results are finally used to discuss the major aerosol processes along the flame centerline.http://www.sciencedirect.com/science/article/pii/S2666352X23000791Flame synthesisTitanium dioxide TiO2Laser-induced incandescence (LII)LII decay timeVolume fraction |
| spellingShingle | J. Yi C. Betrancourt N. Darabiha B. Franzelli Initial interpretation of Laser-induced Incandescence (LII) signals from flame-generated TiO2 particles: Towards a quantitative characterization of the flame synthesis processes Applications in Energy and Combustion Science Flame synthesis Titanium dioxide TiO2 Laser-induced incandescence (LII) LII decay time Volume fraction |
| title | Initial interpretation of Laser-induced Incandescence (LII) signals from flame-generated TiO2 particles: Towards a quantitative characterization of the flame synthesis processes |
| title_full | Initial interpretation of Laser-induced Incandescence (LII) signals from flame-generated TiO2 particles: Towards a quantitative characterization of the flame synthesis processes |
| title_fullStr | Initial interpretation of Laser-induced Incandescence (LII) signals from flame-generated TiO2 particles: Towards a quantitative characterization of the flame synthesis processes |
| title_full_unstemmed | Initial interpretation of Laser-induced Incandescence (LII) signals from flame-generated TiO2 particles: Towards a quantitative characterization of the flame synthesis processes |
| title_short | Initial interpretation of Laser-induced Incandescence (LII) signals from flame-generated TiO2 particles: Towards a quantitative characterization of the flame synthesis processes |
| title_sort | initial interpretation of laser induced incandescence lii signals from flame generated tio2 particles towards a quantitative characterization of the flame synthesis processes |
| topic | Flame synthesis Titanium dioxide TiO2 Laser-induced incandescence (LII) LII decay time Volume fraction |
| url | http://www.sciencedirect.com/science/article/pii/S2666352X23000791 |
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