Enhanced Photoelectrocatalytic Performance Using Chalcogenide Te/TiO 2 /Ti Nanotube Array Based on COD Analyses for Water Treatment Applications

The effect of Te doping of the TiO 2 /Ti nanotube arrays (NTAs) on the photoelectrochemical chemical oxygen demand (COD) detection has been investigated. It is found that the Te doping has enhanced the photoelectrocatalytic properties of the TiO 2 /Ti NTAs electrode. This indicated by the linearity, accuracy, and repeatability of measurement of the test compounds chemicals. The Te-TiO 2 /Ti NTAs shows an excellent linearity to all test compounds up to 10 μM of concentration. It is only up to 5 μM in pristine TiO 2 /Ti NTAs system. In term of accuracy, the Te-TiO 2 /Ti NTAs electrode can provide the measurement accuracy of up to 100% fit to the theoretical value for all test compound chemical. It is only less than 80% for TiO 2 /Ti NTAs electrode. Meanwhile, the repeatability of measurement for the electrode, the Te-TiO 2 /Ti NTAs exhibits 1.8% RSD value, which is lower than the pristine TiO 2 /Ti NTAs, i.e., 2%. The enhancement of the photoelectrocatalytic properties of the TiO 2 by Te doping is due to the lowering of electron and hole recombination during the photoactivation, promoting massive surface reaction with organic compounds and improving the sensing sensitivity. The Te-TiO 2 /Ti NTAs should find the extensive application of PECOD detection of organic contamination in the environment.