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Iron oxide Fe2O3nano-particle powder is investigated by laser-induced breakdown spectroscopy (LIBS). Laser ablation of loose Fe2O3powder (density 0.43 g cm−3) leads to the ejection of particles and generates a plasma channel along the laser beam path. LIBS spectra are obtained by spatially integrated and time-gated measurement in flushed N2gas background. A simple powder delivery system allows for investigation of the nano-particle powder directly without any pre-treatment and fixation of the loose material. The Saha–Boltzmann analysis of spectra yields plasma temperature T= (10250 ± 200) K and electron density Ne= (11 ± 3) × 1016cm−3for the loose Fe2O3powder and for pressed Fe2O3powder pellets that are investigated for comparison. LIBS analysis of more than 20 different powder samples establishes calibration curves for Al, Si, Ni and Mn element impurities. The limits of detection derived from such curves are 8, 15, 66 and 860 ppm for Al, Si, Ni and Mn, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Time-resolved photography was employed to study plasma dynamics and particle ejection of laser-irradiated iron oxide materials. Nano-particle powder, pressed powder pellets and sintered ceramics were ablated in air and Ar gas background by means of short laser pulses (Nd:YAG laser wavelength λ =1064nm and pulse duration τ L ≈6ns; KrF laser λ =248nm and τ L ≈20ns). Plasma plume dynamics significantly depended on sample morphology. The ejection of non-luminous particles up to several hundreds of microseconds after the laser pulse was observed for powder and pressed powder target materials. Laser-induced breakdown spectroscopy (LIBS) was employed for element analysis of iron oxide powders, pressed pellets and sintered ceramics. LIBS spectra of the different targets were comparable to each other and qualitatively independent of target morphology. [Copyright &y& Elsevier]