Study of a novel chromogenic system of Mn2+–fluorone–carbon nanotubes

A novel application of carbon nanotubes (CNTs) in the field of chromogenic reactions is described. The results show that absorption of manganese by phenyl fluorone (PF) can be improved by the addition of a nanomaterial. Comparative experiments prove that the absorption of the complex was increased by 45.9% in the presence of CNTs due to the presence of the intact conjugated system; this is higher than that found with carboxylic CNT (c-CNTs). Furthermore, the steric hindrance effects of fluorone and the effect of the order of additional reactants were tested. This method has been successfully applied to determine the content of manganese in drinking water.