Novel One-Dimensional Organic–Inorganic Polyoxometalate Hybrids Constructed from Heteropolymolybdate Units and Copper–Aminoacid Complexes

Two unique organic–inorganic
hybrid heteropolymolybdates
with copper–aminoacid complexes [Cu­(arg)2]2[(CuO6)­Mo6O18(As3O3)2]·4 H2O (1) and
[Cu­(arg)2]3[TeMo6O24]·8H2O (2) (arg = l-arginine) have been prepared
under the 110 °C hydrothermal environments and structurally characterized
by elemental analyses, IR spectra, thermogravimetric (TG) analyses,
and single-crystal X-ray diffraction. 1 stands for the
first one-dimensional (1D) chain organic–inorganic hybrid arsenomolybdate
constructed from lantern-shaped [(CuO6)­Mo6O18(As3O3)2]4– units through dinuclear [Cu2(arg)4]4+ connectors, whereas 2 represents an unprecedented 1D
chain organic–inorganic hybrid telluromolybdate built by Anderson-type
[TeMo6O24]6– fragments via
trinuclear [Cu3(arg)6]6+ bridges.
Variable-temperature magnetic susceptibilities of 1 and 2 have been investigated and both illustrate the weak antiferromagnetic
coupling within copper centers mediated by the carboxyl groups of
arg ligands. Moreover, the solid-state electrochemical and electrocatalytic
properties of 1 have been carried out in 1 mol L–1 H2SO4 aqueous solution by entrapping
it in a carbon paste electrode. 1 displays apparent electrocatalytic
activities toward the reduction of nitrite and bromate.