摘要
An organic-inorganic hybrid Fe^(Ⅲ)–Pr^(Ⅲ)-included 2-germano-20-tungstate[Pr(H_(2)O)_(8)]2 H_(2)[Fe_(4)(H_(2)O)_(4)(pca)_(4) Ge_(2)W_(20)O_(72)]•34H_(2)O(Hpca=2-pyridinecarboxylic acid)(1)was hydrothermally prepared.Its polyoxoanion comprises one tetra-Fe^(Ⅲ)incorporated[Fe_(4)(H_(2)O)_(4)(pca)_(4) Ge_(2)W_(20)O_(72)]^(8-)hybrid entity and two[Pr(H_(2)O)_(8)]^(3+)ornamental cations.The[Fe_(4)(H_(2)O)_(4)(pca)4 Ge_(2)W_(20)O_(72)]^(8-)2-germano-20-tungstate entity can be regarded as an infrequent S-type[Ge_(2)W_(20)O_(72)]^(16-)cluster pocketed by four[Fe(H_(2)O)(pca)]2+cations.The S-type[Ge_(2)W_(20)O_(72)]16-cluster could be imagined as condensation of two divacant Keggin[α-GeW _(10)O_(37)]^(10-)segments by sharing two atoms.It is of interest is that carboxyl O and pyridine N atoms on pca ligands concurrently bind with Fe ^(3+)cations in a five-membered heterocyclic fashion to increase the stability of the whole structure.Furthermore,the electrochemical biosensing properties of 1 as the modified electrode material have been investigated for detecting norepinephrine(NPP),showing a low detection limit of 3.25μmol/L.This work not only enriches structures of heterometallic german-otungstates(GTs),but also expands applications of polyoxometalates(POMs)in the electrochemical biosensing field.
基金
supported by the National Natural Science Foun-dation of China(Nos.21871077,21671054,21771052,22071042)
the Program for Innovation Teams in Science and Technology in Universities of Henan Province(No.20IRTSTHN004).
