Organic–Inorganic Hybrid Cerium-Encapsulated Selenotungstate Including Three Building Blocks and Its Electrochemical Detection of Dopamine and Paracetamol

Abstract

A novel organic-inorganic hybrid cerium-encapsulated selenotungstate comprising three polyoxotungstate building units Na₁₆H₆{[Ce₃W₄O₁₀(H₂O)₉(CH₃COO)₃]₂(Se₂W₇O₃₀)(B-α-SeW₉O₃₃)₄}·(C₅H₈NBO₃)·119H₂O (<b>1</b>) was synthesized by the portfolio approach of an in situ self-assembly reaction and step-by-step synthesis. The hybrid polyoxoanion of <b>1</b> is constructed from an acetate-coordinated heterometallic {[(Ce₃W₄O₁₀)(H₂O)₉(CH₃COO)₃]₂(Se₂W₇O₃₀)}¹⁰⁺ core encompassing four trilacunary [B-α-SeW₉O₃₃]^8- subunits. Interestingly, the heterometallic core contains a remarkable [Se₂W₇O₃₀]^10- building block in which seven W^VI atoms form a W₇ plane and two Se^IV atoms are situated on two opposite faces of the W₇ plane. In addition, the electrochemical performances of the <b>1</b>@CFMCN composite (CFMCN: carboxyl-functionalized multiwalled carbon nanotube) were investigated. The <b>1</b>@CFMCN/GCE (GCE: glass carbon electrode) sensor demonstrates a promising potential in electrochemically sensing dopamine (DPA) or paracetamol (PCM) or even simultaneously detecting DPA and PCM with low limits of 0.053 μM for DPA and 2.03 μM for PCM over a wide linear range at high sensitivity.