OPTIMIZATION OF ELECTROCHEMICAL DEPOSITION OF NOBLE-METALS FOR PERMANENT MODIFICATION IN GRAPHITE-FURNACE ATOMIC-ABSORPTION SPECTROMETRY

Palladium, rhodium and iridium were investigated as chemical modifiers following their electrodeposition on the graphite surface. Conditions for electrodeposition were optimized to find the best analytical perf ormance. Cadmium was used as a test element in this study. Using modif ied tubes, maximum pyrolysis temperatures were 800 degrees C with Ir a s modifier, 900 degrees C with Pd, 1000 degrees C with Pd + Ph, and 11 00 degrees C with Ph alone. The modified tubes exhibit a long-term per formance, which indicates an advantage in use of the electrodeposition of noble metals as permanent modification. (C) 1998 Elsevier Science B.V. All rights reserved.