Synthesis, characterization and antiviral activity of nickel-substituted rare earth molybdosilicic heteropoly blues
A series of novel heteropoly blues, Ln2H2[SiMo11Ni(H2O)O39] · nH2O (Ln = La, Ce, Pr, Nd, Sm, or Gd), had been prepared and characterized by elemental analysis, i.r., u.v., c.v., t.g.–d.t.a., XPS, 29Si-n.m.r., electrochemistry and magnetic susceptibility. Compared with non-reduced heteropolyoxometallates, the heteropoly blue anion in Ln2H2[SiMo11Ni(H2O)O39] · nH2O still retains the α-Keggin structure but with a slight distortion, with Ni and Mo atoms distributed statistically in the crystal. The antiviral activities of these complexes have been studied using tomato mosaic virus. Ln2H2[SiMo11Ni(H2O)O39] · nH2O show excellent antivirus activities, and the cure rate reaches to 80–90%.