RT Journal Article
T1 Optical trapping as a morphologically selective tool for in-situ LIBS elemental characterization of single nanoparticles generated by laser ablation of bulk targets in air
A1 Purohit, Pablo
A1 Fortes-Román, Francisco Javier
A1 Laserna-Vázquez, José Javier
K1 Nanopartículas
AB In the present work, authors introduce a shape-specific methodology for evaluating the full elemental composition of single micro and nanoparticles fabricated by laser ablation of bulk targets. For this purpose, bronze samples were directly ablated within an ablation cell, originating dry aerosols consisting of multielemental particles. The in-situ generated particles were first optically trapped using air at atmospheric pressure as medium, and then probed by LIBS. A key aspect of this technology is the circumvention of possible material losses owed to transference into the inspection instrument while providing the high absolute sensitivity of single-particle LIBS analysis. From results, we deepen the knowledge in laser-particle interaction, emphasizing fundamental aspects such as matrix effects and polydispersity during laser ablation. The dual role of air as the atomization and excitation source during the laser-particle interaction is discussed on the basis of spectral evidences. Fractionation was one of the main hindrances as it led to particle compositions differing from that of the bulk material. To address possible preferential ablation of some species in the laser-induced plasma two fluence regimes were used for particle production, 23 and 110 J/cm2. LIBS analysis revealed a relation between chemical composition of the individual particles and their sizes. At 110 J/cm2, 65% of the dislodged particles were distributed in the range 100-500 nm, leading to higher variability of LIBS spectra among the inspected nanoparticles. In contrast, at 23 J/cm2, around 30 % of the aerosolized particles were larger than 1 m. At this regime, the composition resembled better to the bulk material. Therefore, we present a pathway to evaluate how adequate the fabrication parameters are towards yielding particles of a specific morphology while preserving compositional resemblance to the parent bulk sample.
PB American Chemical Society
YR 2021
FD 2021-01-05
LK https://hdl.handle.net/10630/28801
UL https://hdl.handle.net/10630/28801
LA eng
NO Pablo Purohit, Francisco J. Fortes, and J. Javier Laserna Analytical Chemistry 2021 93 (4), 2635-2643 DOI: 10.1021/acs.analchem.0c04827
NO Research funding by the Spanish Ministerio de Economia y Competitividad under Project CTQ2017–82137P is acknowledged. Pablo Purohit acknowledges the concession of his FPI fellowship, associated with the project CTQ2014–56058P.
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 20 ene 2026