Optimal conditions for europium and samarium determination in cathodoluminophors by inductively coupled plasma atomic emission spectrometry

CaS: Eu, and CaS: Eu, Sm, luminophors are red-emitting cathodoluminophors. These materials are of great importance due to their high efficiency and ch romaticity for electroluminescence and cathodoluminescence display. For the synthesis of luminophors, required amounts of rare earth elements as dopan ts in high purity grade CaS were employed. For the determination of europiu m and samarium in the luminophors, a sequential PU 7000 (Philips) inductive ly coupled plasma atomic emission spectrometer (ICP-AES) was used. The euro pium emission lines at 381.967 nm and at 412.970 nm and the samarium emissi on lines at 359.260 nm and at 356.827 nm were compared. The effect of the c hanges of the forward radio frequency power coupled into the plasma on the emission intensity of various Eu and Sm spectral lines was investigated. Th e matrix effect due to calcium was studied and a scan of different emission lines of Eu and Sm was carried out. The different samples of cathodolumino phors containing 0.005-0.16 at.% of Eu and 0.02-0.04 at.% of Sm were analys ed and the precision (RSD) ranged from 1.1 to 1.6%.