A Lanthanide-Incorporated Phospho(III)tungstate Aggregate Constructed from [HPWO] and [WO] Building Blocks and Its Nanocomposite with CdS for Ultrasensitive Photoelectrochemical Detection of Oxytetracycline.

A novel tartronic acid decorated hexa-Ce-incorporated phospho(III)tungstate aggregate (CHNO)NaH[(HPWO)[WO](HTAD)(HO)WCeHPO]·84HO (, HTAD = tartronic acid) was synthesized by a one-step assembly strategy. Its main skeleton is constructed from two [WO] fragments, two [HPWO] segments and one HTAD-ornamented dodecanuclear heterometallic [WCeHPO(HTAD)(HO)] cluster. In the structure, the [HPO] groups not only work as the heteroatom template to induce the formation of lacunary [HPWO] segments but also function as the connector to bridge Ce cations. With the help of a reaction strategy of combining ultrasonication treatment with the continuous ion layer adsorption method, the /CdS composite was constructed and exhibits prominent photoelectrochemical activity. The /CdS composite was used as a photoelectrochemical sensor for oxytetracycline detection at 0 V (vs Ag/AgCl), which displays excellent properties with quick response and low limit of detection (0.042 nM). This work can provide some helpful references in the construction of novel P-induced polyoxometalates consisting of different building blocks and can extend the applications of polyoxometalate-based nanocomposites into photoelectrochemical detection for antibiotics as well as biomolecules.