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

•Copper–lanthanide heterometallic germanotungstate.•IR spectra of copper–lanthanide heterometallic germanotungstates.•Photoluminescence spectra of germanotungstates.•The electrocatalytic activity for nitrite reduction.

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.

Graphical abstractTwo 1-D copper–lanthanide heterometallic germanotungstate hybrids have been synthesized and IR spectra, the photoluminescence spectra and the electrocatalytic activity for nitrite reduction of 1 have been studied.Figure optionsDownload full-size imageDownload as PowerPoint slide