摘要
该文采用自组装的方法制备了量子点 CdS 掺杂的 TiO_2(QD-CdS/TiO_2)光电化学传感器,并将其用于化学需氧量(COD)的测定。在紫外光照射下,QD-CdS/TiO_2光电化学传感器和有机物之间的电荷传递过程可以通过光生电流的形式表现出来。QD-CdS 的掺杂使得该复合薄膜表现出比 TiO_2更好的光电催化活性,提高了 COD 测定的灵敏度和线性范围。以葡萄糖为响应底物,考察了 QD-CdS/TiO_2光电化学传感器的光电催化行为,结果表明该传感器的光电流信号与 COD 值在15.0～600.0 mg/L 浓度范围内有很好的线性响应,相关系数为0.9917。用于测定实际水样中 COD 的测定,结果与传统的重铬酸钾法相比有较好的相关性。
In this work, a QD - CdS/TiO2 photoelectrochemical sensor was prepared and applied to chemical oxygen demand （COD） determination based on the charge transfer on the interface of QD - CdS/TiO2 film electrode and the passing solution. With a positive bias potential of 0. 4 V （ vs. Ag/AgCl） applied to the sensor and an 11 - W quartz UV lamp illuminating it, photocurrent, was recorded and its change （△Iphoto） caused by the detected sample was calculated to characterize the COD value of the sample. Under the optimizing conditions, the sensor responded linearly to the COD of D - glucose solution in the range of 15.0 -600. 0 mg/L and the lowest limit of detection is 6. 5 mg/L.
出处
《化学传感器》
CAS
2005年第4期16-21,共6页
Chemical Sensors
基金
国家自然科学基金(No.20327001)
科技攻关(No.2004BA210A07)资助项目
