Synthesis, characterisation and voltammetric study of a beta-Keggin-type [PW12O40](3-) complex

The Keggin-type beta-[PW12O40](3-) complex was prepared, and the voltammetr ic behavior was compared with that of the Keggin-type alpha-[PW12O40](3-) c omplex. Both complexes underwent a four-step one-electron reduction in CH3C N where no protonation accompanied reduction. With the addition of CF3SO3H, the one-electron reduction waves were converted into two two-electron wave s, followed by an ill-defined wave. The addition of water to the CH3CN + CF 3SO3H system caused the first two-electron wave to split into two one-elect ron waves. The effect of acid or water on the voltammetric behavior is disc ussed also. (C) 1999 Elsevier Science S.A. All rights reserved.