A 3-D framework based on mono-copper~(II) substituted silicotungstate units [Cu(dap)2(H2O)]2[Cu(dap)2][α-SiW_(11)CuO_(39)]·2H2O

摘要

A 3-D mono-copper~(II) substituted silicotungstate [Cu(dap)2(H2O)]2[Cu(dap)2][α-SiW_(11)CuO_(39)]·2H2O (1) has been hydrothermally synthesized by reaction of Na_(10)[A-α-SiW9O_(34)]·18H2O, CuCl2·2H2O, LaCl3 and dap (dap = 1,2-diaminopropane) and characterized by elemental analyses, IR spectrum, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. To our knowledge, 1 represents the first 3-D four-connected framework with the Schlafii symbol of 6~4 · 8 · 10 that is built by mono-copper" substituted silicotungstate units in polyoxometalate chemistry. The TG curve of 1 indicates two steps of weight loss between 25 and 750 °C Furthermore, the solid-state electrochemical and electro-catalytic properties of 1 have been measured in 0.5 mol·L~(-1) Na2SO4 + H2SO4 aqueous solution by entrapping it in a carbon paste electrode. 1 displays evident electro-catalytic activities toward the nitrite and bromated reduction.