Electrochemically reduced phytic acid-doped TiO2 nanotubes for the efficient electrochemical degradation of toxic pollutants

Abstract Element-doped TiO2 nanotube arrays (TNAs) with optimized active sites provide an effective approach for significantly improving electrocatalytic performance. The challenges in such construction mainly include selection of green dopant and control of active sites. Herein, we present phytic acid as a phosphorus source for P-doped TNAs. An oxygen vacancy (Ov) and P co-doped TNAs (P-TiO2−y) was prepared as an electrochemical oxidation anode. P-TiO2−y exhibits excellent degradation activity due to the formation of Ti-O-P bonds and generation of Ov. P-doping was beneficial in improving the oxygen evolution potential of the electrode, which would be benefit for electrocatalytic degradation of pollutants. Using the P-TiO2−y anode with a current density of 10 mA/cm2 for tetracycline degradation, after a 3 h treatment, the removal rate, chemical oxygen demand and total organic carbon removal rates were 100%, 90.32% and 76.60%, respectively. The P-TiO2−y also has excellent degradation performance for phenol, hydroquinone, p-nitrophenol and metronidazole.