Reduced phosphomolybdate as photoassisted electrochemical crystalline sensor for trace Cr(VI) detection

作者：Hao Song, Meng-Si Guo, Jiefei Wang, Yuqing Liu, Hao‐Xue Bi, Jing Du, Wenting An, Yuan‐Yuan Ma, Zhangang Han · 发表于：Polyoxometalates · 年份：2024 · DOI：10.26599/pom.2024.9140065 · 被引用次数：43 · 研究领域：Polyoxometalates: Synthesis and Applications、Metal-Organic Frameworks: Synthesis and Applications、Electrochemical Analysis and Applications

Sensitive and efficient detection technology for trace toxic hexavalent chromium (Cr(VI)) in water is urgent. Herein, an hourglass-type phosphomolybdate-based metal-organic network was hydrothermally synthesized with formula of [Na 0.5 Cu 5.5 (H 2 O) 2 (btmbp) 4 ][Mn(H 2 O) 3 ] 2 {Mn[H 6 P 4 Mo 6 O 31 ] 2 }·10H 2 O ( 1 , btmbp= 4,4′-bis((1H-1,2,4-triazol-1-yl)methyl)biphenyl). Crystal network consists of ladder-like two-dimensional layer-like structure constructed by the vertical connections of 1-D [Na 0.5 Cu 5.5 (H 2 O) 2 (btmbp) 4 ] 6+ metal-organic chains and 1-D inorganic polyanionic chains. Compound 1 exhibits good excellent electrochemical property and wide light absorption that can absorb visible light to accelerate the electron transfer in redox process. When serving as a photo-assisted electrochemical (PAEC) sensor for trace Cr(VI) detection, compound 1 exhibits high sensitivity of 330.5 μA·μM -1 and low detection limit of 0.95 nM (98.79 ppt) along with high anti-interference ability and excellent PAEC detection stability. These results are superior to most reported POM-based sensors, and even comparable to noble-metal sensors, far satisfying WHO standards for Cr(VI) concentration in drinking water. This work provides a new promising photoelectrochemical sensor material for actual environmental pollutant monitoring.