Electrothermal vaporization, part 2: surface chemistry

This review is the second of a two-part series on evaluation of vaporizatio n and atomization processes in electrothermal vaporizers (ETV), focused spe cifically on surface chemistry in ETVs. Laser desorption mass spectrometry and differential scanning calorimetry are used to investigate vaporization of Mg, Ca, Sr, Ba, and Ni. Graphite, AI, and Ta were used as the vaporizer substrate material to elucidate potential pathways with regard to surface c hemistry. The results presented in parts 1 and 2 of this publication series clearly illustrate the role of surface chemistry when a substrate is heate d to yield atomic or molecular vapors. Depending on the attributes of the s ubstrate material and the extent of surface modification, the surface-induc ed processes that ultimately define the quantity and the nature of gas phas e species includes liquid-solid interactions, solid-solid interactions, cat alysis, diffusion, migration, heterogeneous reactions and intercalation. (C ) 2000 Elsevier Science B.V. AU rights reserved.