Syntheses, structures, spectroscopic and electrochemical properties of two 1D organic-inorganic CuII-LnIII heterometallic germanotungstates

Two organic-inorganic hybrid copper-lanthanide heterometallic germanotungstates KNa2H7[enH2]3[Cu(en)2(H2O)]2[Cu(en)2]2{Cu(en)2[Eu(α-GeW11O39)2]2}·13H2O (1) and Na2H4[Cu(en)2(H2O)]2[Cu(en)2]6[Cu(en)2]{Cu(en)2[La(α-GeW11O39)2]2}·12H2O (2) have been hydrothermally synthesized by reaction of K8Na2[A-α-GeW9O34]·25H2O with CuCl2·2H2O and EuCl3/LaCl3 in the presence of en (en=ethylenediamine) and structurally characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. 1 exhibits the 1D chain motif built by tetrameric {[Cu(en)2(H2O)]2[Cu(en)2]2{Cu(en)2[Eu(α-GeW11O39)2]2}}(16-) moieties through square antiprismatic K(+) cations while 2 displays the 1D architecture made by tetrameric [[Cu(en)2]6[Cu(en)2]{Cu(en)2[La(α-GeW11O39)2]2}](10-) units via octahedral [Cu(en)2](2+) cations. Furthermore, the solid-state electrochemical and electrocatalytic properties of 1 have been investigated and 1 indicates the good electrocatalytic activity for nitrite reduction. In addition, the photoluminescence property of 1 has been investigated.