Spectral, temporal, and volumetric measurement of phase-selective laser-induced breakdown spectroscopy on TiC nanoparticles

Phase-selective laser-induced breakdown spectroscopy (PS-LIBS) is an emerging technique for in situ diagnostics of nanoparticle distribution in aerosols, potentially also distinguishing between particle phases, e.g., localizing gas-to-solid phase transitions. Its application has so far been largely confined to point measurement or one- or two-dimensional imaging, with limited exploration of spectral and temporal dynamics. In this study, a streak camera-coupled spectrometer was employed to capture time-resolved spectra of PS-LIBS for titanium-based nanoparticle aerosols. By integrating this approach with excitation in extended probe volumes and computed tomography principles, we achieved volumetric measurement of PS-LIBS within a microwave plasma reactor during the synthesis of TiC nanoparticles. This advancement demonstrates the potential of PS-LIBS in in situ diagnostics in nanoparticle synthesis.