Luo Lijie, Yang Yewen, Chen Shu, Zhang Peisheng, Zeng Rongjin
Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China.
Molecules. 2024 Jan 27;29(3):614. doi: 10.3390/molecules29030614.
This paper presents the development of a photoelectrochemical sensor for hypochlorous acid (HOCl) detection, employing a phenothiazine-based organic photosensitizer (Dye-PZ). The designed probe, Dye-PZ, follows a D-π-A structure with phenothiazine as the electron-donating group and a cyano-substituted pyridine unit as the electron-accepting group. A specific reaction of the phenothiazine sulfur atom with HOCl enables selective recognition. The covalent immobilization of Dye-PZ onto a titanium dioxide nanorod-coated fluorine-doped tin oxide electrode (FTO/TiO) using bromo-silane coupling agent (BrPTMS) resulted in the fabrication of the photoanode FTO/TiO/BrPTMS/Dye-PZ. The photoanode exhibited a significant photoresponse under visible-light irradiation, with a subsequent reduction in photocurrent upon reaction with HOCl. The oxidation of the phenothiazine sulfur atom to a sulfoxide diminished the internal charge transfer (ICT) effect. Leveraging this principle, the successful photoelectrochemical sensing of HOCl was achieved. The sensor showed high stability, excellent reproducibility, and selective sensitivity for HOCl detection. Our study provides a novel approach for the development of efficient photoelectrochemical sensors based on organic photosensitizers, with promising applications in water quality monitoring and biosensing.
本文介绍了一种用于检测次氯酸（HOCl）的光电化学传感器的研制，该传感器采用了一种基于吩噻嗪的有机光敏剂（染料-PZ）。所设计的探针染料-PZ具有D-π-A结构，以吩噻嗪作为供电子基团，氰基取代的吡啶单元作为受电子基团。吩噻嗪硫原子与HOCl的特定反应实现了选择性识别。使用溴硅烷偶联剂（BrPTMS）将染料-PZ共价固定在二氧化钛纳米棒包覆的氟掺杂氧化锡电极（FTO/TiO）上，从而制备了光阳极FTO/TiO/BrPTMS/染料-PZ。该光阳极在可见光照射下表现出显著的光响应，与HOCl反应后光电流随后降低。吩噻嗪硫原子氧化为亚砜减弱了内电荷转移（ICT）效应。利用这一原理，成功实现了对HOCl的光电化学传感。该传感器对HOCl检测表现出高稳定性、优异的重现性和选择性灵敏度。我们的研究为基于有机光敏剂的高效光电化学传感器的开发提供了一种新方法，在水质监测和生物传感方面具有广阔的应用前景。
