Phosphomolybdates for Dual-Mode Photoelectrochemical Sensing toward Trace Chromium(VI) and Tetracycline

作者：Hao‐Xue Bi, Xiujuan Zhang, Jing-Yan He, Yuqing Liu, Yuan‐Yuan Ma, Zhangang Han · 发表于：Inorganic Chemistry · 年份：2024 · DOI：10.1021/acs.inorgchem.4c02363 · 被引用次数：17 · 研究领域：Polyoxometalates: Synthesis and Applications、Advanced Nanomaterials in Catalysis、Electrochemical sensors and biosensors

Highly sensitive photoelectrochemical (PEC) sensors for trace carcinogens, such as heavy metal chromium(VI) [Cr(VI)] and antibiotic tetracycline (TC) are crucial. Herein, by integration of photoactive and redox phosphomolybdates with conjugated organic components, types of dual-mode PEC sensors were synthesized for sensing trace Cr(VI) and TC pollutants, with formulas of (H 2 bimb) 2 [Co 2 (bimb) 1.5 ][Co(H 2 O) 4 ][Co(P 4 Mo 6 O 31 H 6 ) 2 ]·6H 2 O ( 1 ), (H 2 bib) 2 [Co(H 2 O) 3 ][Co 2 (H 2 O) 5 ][Co(P 4 Mo 6 O 31 H 6 ) 2 ]·9H 2 O ( 2 ), and (H 2 bib) 6 [Co(Hbib) 2 (H 2 O) 5 ][Co(P 4 Mo 6 O 31 H 7 ) 2 ] 2 ·15H 2 O ( 3 ), where bimb represents 1,4-bis(1-imidazolyl)benzene and bib is 4,4′-bis(imidazolyl)bibphenyl. Hybrid 1 consisted of a three-dimensional framework structure constructed by Co{P 4 Mo 6 } 2 clusters and one-dimensional (1D) {Co-bimb} chains, hybrid 2 exhibited 1D Co ion-bridged Co{P 4 Mo 6 } 2 chains hydrogen-bonding with [H 2 bib] 2+ cations, and hybrid 3 showed a discrete hybrid structure built upon a Co{P 4 Mo 6 } 2 cluster modified by the {Co-bib} unit. Hybrids 1 – 3 displayed wide spectral absorption and excellent electrochemical redox properties, enabling dual-mode PEC responses to Cr(VI) reduction and TC oxidation. For Cr(VI) detection, hybrids 1 – 3 exhibited high sensitivities of 364.40, 225.72, and 124.29 μA·μM –1 as well as “nM” level detection limits (LODs) of 4.9, 10.0, and 11.0 nM, respectively. For TC detection, the sensitivities of hybrids 1 – 3...