The chemical oxygen demand (COD) online monitoring sensor, based on the spectral absorption, shows outstanding advantages in water quality monitoring, pollution source tracing, and environmental protection inspection. However, there are several factors that influence the stability and accuracy of the sensor detection in practical applications. Therefore, they must be carefully considered. This research analyzes the impact of changes in physical characteristics, chemical composition, and external environmental interference on the output result of the optical COD sensor systematically and comprehensively, from different fields including electronic technology, sensor technology, composition analysis, and environmental condition analysis, through both theoretical and experimental approaches. This study will provide guidance for the scientific research, product development, and upgrading of the optical water quality sensor, and provide reference for the long-term use, operation, and maintenance of the sensor.
| [1] |
2024 bulletin on the state of ecological environment China[R]. The Ministry of Ecology and Environment of China, 2025.
|
| [2] |
Qi X, Zhang Y, Yuan D, et al. An optical path multiplexing fiber sensor for ultra-low COD levels measurement using UV-Vis spectrometry. IEEE sensors journal, 2024, 24798359842. J]
|
| [3] |
Daniella S, Kristina B, Wenny N, et al. Ultraviolet/visible absorbance trends for beverages under simulated rinse conditions and development of data-driven prediction model. Food control, 2023, 146: 109530. J]
|
| [4] |
James C. Advances in chemistry research, 2023, Hauppauge: Nova Science Publishers[M]
|
| [5] |
Joes M, Alatzne C, Maria P, et al. Problems of instrumental analytical chemistry: a hands-on guide, 2017, Hackensack: World Scientific Publishing Company[M]
|
| [6] |
Thomas J, Paris D. CRC handbook of basic tables for chemical analysis, 20032nd ed.AbingdonTaylor and Francis, CRC Press[M]
|
| [7] |
Miran B, Franjo P, Bostjan L. LED light sources: a survey of quality-affecting factors and methods for their assessment. Measurement science & technology, 2008, 1912122002. J]
|
| [8] |
Penzel S, Mayer T, Goblirsh T, et al. A novel turbidity compensation method for water measurements by UV/Vis and fluorescence spectroscopy. Measurement, 2025, 239: 115447. J]
|
| [9] |
Zhao J. Research on portable COD detector based on UV-Vis spectroscopy technology, 2024, Changchun: Jilin University[D]
|
| [10] |
Hu Y, Wen Y, Wang X. Novel method of turbidity compensation for chemical oxygen demand measurements by using UV-vis spectrometry. Sensors and actuators B: chemical, 2016, 227: 393-398. J]
|
| [11] |
Dong J, Tang J, Wu G, et al. A turbidity-compensation method for nitrate measurement based on ultraviolet difference spectroscopy. Molecules, 2023, 28: 250. J]
|
| [12] |
Zhang Y, Xu C, Qin, et al. Research on COD measurement method based on UV-Vis absorption spectra of transmissive and reflective detection systems. Frontiers in environmental science, 2023, 11: 1175363. J]
|
| [14] |
Zhang Y, Chen P, Liu Y, et al. Temperature compensation study of micro-LED by machine learning. SID symposium digest of technical papers, 2024, 55112851288. J]
|
| [15] |
Cai J. Design of water quality COD online detection system based on ultraviolet-visible spectroscopy, 2021, Taiyuan: Taiyuan University of Technology[D]
|
| [16] |
Li J, Ding Y, Lu Y, et al. The influence and compensation of environmental factors (pH, temperature, and conductivity) on the detection of chemical oxygen demand in water by UV-Vis spectroscopy. Applied sciences, 2025, 15: 1694. J]
|
| [17] |
Zhou K, Liu Z, Cong M, et al. Analysis on influencing factors of detecting chemical oxygen demand in water by three-dimensional spectroscopy. Optoelectronics letters, 2022, 1812749754. J]
|
| [18] |
Li H. The effects of conjugated molecular structures on absorption spectra and the charge transport of perovskite, 2019, Shandong: Shandong University[D]
|
Rights & permissions
Tianjin University of Technology