LASER-INDUCED BREAKDOWN SPECTROSCOPY (LIBS) AS AN ANALYTICAL TOOL FORTHE DETECTION OF METAL-IONS IN AQUEOUS-SOLUTIONS

Laser induced breakdown spectroscopy (LIBS) is applied to analyze aque ous solutions of Li+, Na+, Ca2+, Ba2+, Pb2+, Cd2+, Hg2+ and Er3+ and s uspensions of ErBa2Cu3O particles (d = 0.2 mu m). An excimer (308 nm) pumped dye laser with laser pulse at 500 nm and pulse energy at 22 +/- 2 mJ is used to produce plasma in aqueous solution. Plasma emission l ines of the elements are detected by a photodiode array detector. Dete ction limits of the metal ions are 500 mg/l for Cd2+, 12.5 mg/l for Pb 2+, 6.8 mg/l for Ba2+, 0.13 mg/l for Ca2+, 13 mu g/l for Li+ and 7.5 m u g/l for Na+. No mercury and erbium emission can be detected, even at Hg2+ and Er3+ concentrations of up to the g/l range. On the other sid e, for Er in suspensions of ErBa2Cu3Ox particles a more than 10(3) tim es higher sensitivity is found than for dissolved Er3+. This result gi ves a possibility to analyze colloid-borne metal ions with an increase d sensitivity.