This study presents a novel photoelectrochemical (PEC) conversion method for ion-selective electrodes (ISEs) based on CdS semiconductor film. The motivation stems from the need to enhance the sensitivity and precision of ISEs for various analytical applications. We synthesized CdS film on FTO conductive glass via a hydrothermal method and utilized this electrode as the working electrode. Under visible light irradiation, CdS generated photocurrent that is proportional to its applied voltage within a large potential window of ∼0.80 V. Ascorbic acid (AA) effectively inhibited electron-hole complexation, enhancing photocurrent stability. Potential modulation from ISEs acting as the reference electrode further regulated photocurrent generation, demonstrating excellent sensitivity and linearity for a wide range of ion concentrations. The method was validated by detecting serum calcium levels, showing agreement with traditional ISEs potentiometry and ICP-OES methods. This photoelectrochemical conversion strategy offers a promising approach for sensitive and accurate ion detection, with potential applications in clinical diagnostics and environmental monitoring.

中文翻译：

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基于CdS半导体薄膜的离子选择性电极的光电化学转换


本研究提出了一种基于 CdS 半导体薄膜的离子选择电极 (ISE) 的新型光电化学 (PEC) 转换方法。其动机源于提高 ISE 对于各种分析应用的灵敏度和精度的需要。我们通过水热法在FTO导电玻璃上合成了CdS薄膜，并利用该电极作为工作电极。在可见光照射下，CdS 在 ~0.80 V 的大电位窗口内产生与其施加电压成正比的光电流。抗坏血酸 (AA) 有效抑制电子空穴络合，增强光电流稳定性。作为参比电极的 ISE 的电位调制进一步调节了光电流的产生，在各种离子浓度下表现出出色的灵敏度和线性度。该方法通过检测血清钙水平进行了验证，结果与传统 ISE 电位测定法和 ICP-OES 方法一致。这种光电化学转换策略为灵敏、准确的离子检测提供了一种有前景的方法，在临床诊断和环境监测方面具有潜在的应用前景。