Modulation of Intercalation Properties of Copper-Zinc Mixed-Metal Phosphonate Materials

摘要

New layered mixed divalent metal vinylphophonates Cu_(1-x)~IIZn_(x~-)~(II)-(O_3PC_2H_3)·H_2O have been prepared from a range of pre-formed copper-zinc oxides Cu_(1-x)~(II)Zn_x~(II)O obtained by isomorphous substitution of zinc into the tenorite-type structure of Cu~(II)O. The corresponding mixed divalent copper-zinc vinylphosphonates have been characterised by powder X-ray diffractioin, elemental analysis, infrared spectroscopy and thermogravimetric analysis. All compounds have been shown to consist of a single-phase solid solution that crystallises in an monoclinic unit cell, space group P2_1/c with a = 9.86-9.90, b = 7.61-7.64, c = 7.32-7.35 A and beta = 95.9-96 deg, with the exception of the pure zinc vinylphosphate (x = 1), the structure of which is comparable to other Zn~(II)(O_3PR)· H_2O materials. Studies of the intercalation of n-butylamine into the range of copper-zinc vinylphosphonates have demonstrated that significant modulation of the adsorption properties occurs; whereas one mole of amine is intercalated into the pure zinc vinylphosphonate to give Zn~(II)(O_3P-C_2H_3)·(C_4H_9NH_2), for all other members of the series tw molecules of amine are coordinated to give intercalated compounds of composition Cu_(1-x)~(II)Zn_(x~-)~(II)(O_3PC_2H_3)·[(C_4H_9NH_2)_(1-x)(C_4H_9NH_2)_x]_2 from which the amine can be sequentially removed from the different metal sites; this opens up possibilities for further applications of these materials.