Constructing efficient Ti₄O₇/PbO₂ heterostructured photoelectrode for water remediation

Photoelectrocatalytic oxidation (PEC) technology is considered to be an efficient process for the treatment of organic wastewater, and its performance depends on the characteristics of the PEC photoanodes. Therefore, the construction of heterogeneous nanostructured photoelectrodes based on suitable semiconductor materials for fast induced carrier transfer efficiency is essential for a high-performance PEC technique. Herein, titanium suboxide/lead (IV) oxide (Ti₄O₇/PbO₂) ceramic photoelectrode with efficient PEC performance was synthesized by coupling PbO₂ nanospheres with Ti₄O₇ through a hydrothermal method. To maximize the PEC performance of the ceramic electrodes, the Ti₄O₇/PbO₂ nano-heterostructures were optimized by modulating the hydrothermal temperature. The optimized ceramic electrodes possessed a low Tafel slope, a low charge-transfer resistance and a good photocurrent response. Ti₄O₇/PbO₂-110 exhibited an efficient PEC activity (approximately 92.21%) for the degradation of reactive brilliant blue KN-R. The efficient PEC performance of Ti₄O₇/PbO₂-110 arose from the formation of a type II heterojunction between Ti₄O₇ and PbO₂, which achieved efficient photogenerated carrier separation and facilitated the formation of intermediate active species. This work not only validates the efficient performance of Ti₄O₇/PbO₂-110 for PEC water purification but also provides a reference strategy for the preparation of heterostructured ceramic photoelectrodes with a high PEC efficiency.