AUTHOR=Si Hewei , Zhang Xidong , Lin Shiwei 

TITLE=A Simple Flow Injection Sensing System for the Real-Time On-Line Determination of Chemical Oxygen Demand Based on 3D Au-NPs/TiO2 Nanotube Arrays

JOURNAL=Frontiers in Materials

VOLUME=6

YEAR=2019

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2019.00238

DOI=10.3389/fmats.2019.00238

ISSN=2296-8016

ABSTRACT=<p>3D bare TiO<sub>2</sub> nanotube arrays loaded with Au nanoparticles (3D Au-NPs/TNTAs) were prepared to effectively enhance the photoelectrocatalytic properties. A simple flow injection sensing system was proposed for the real-time on-line determination of chemical oxygen demand using the 3D Au-NPs/TNTAs electrode. The proposed photoelectrochemical oxidative degradation principle of the sensing system was analyzed and validated by the representative organic compounds with known COD values at a potential bias 1.5 V under UV illumination. A practical detection limit of the sensing system is 0.18 mg/L and the linear range is 1.92–3,360 mg/L under the optimum conditions. In the experimental process, the sensing system exhibits long-term stability and good reproducibility.</p>