Reduction of Interferences Using Fe-Containing Metal–Organic Frameworks for Matrix Separation and Enhanced Photochemical Vapor Generation of Trace Bismuth

Photochemical vapor generation (PVG) has emerged as a promising sample introduction method for atomic spectrometry in recent years. Despite its great success, a major impediment for the wide application of PVG is the interferences from the coexisting ions, especially transition-metal ions. In this work, iron and 1,3,5-benzenetricarboxylic (Fe-BTC), a Fe-containing metal–organic framework (MOF) material, was synthesized and first used as a platform integrating the sample matrix separation, preconcentration, and photocatalysis for the highly selective determination of elements by PVG. Bismuth was selected as a model analyte. Fe-BTC served not only as the photocatalyst for the PVG of Bi3+ but also as an efficient absorbent for the separation of analytes from the sample matrix. Compared with the previous PVG system, the performance of tolerating interferences toward coexisting ions of the proposed method has been greatly improved after using Fe-BTC-based matrix separation. Thus the excess of 10 mg L–1 of Co2+...