Strategy for enhancing the electrocatalytic performance of Ti/β-PbO2 anode: Optimizing SnO2 intermediate layer by Cs doping and application for the efficient removal of mixed fluoroquinolones
In this paper, the electrocatalytic performance of Ti/β-PbO 2 anode was improved by doping Cs into SnO 2 intermediate layer (Ti/Cs-SnO 2 /β-PbO 2 ) for the efficient degradation of fluoroquinolone wastewater. Compared with the conventional Ti/Sb-SnO 2 /β-PbO 2 anode, Cs-SnO 2 with the rougher surface increased the deposition amount and the thickness of β-PbO 2 active layer, thus forming the denser PbO 2 coating with smaller particle size and exposing more active sites. The partial replacement of Sn by Cs with the smaller ion radius induced the deformation of crystal lattice of SnO 2 , which further led the outer β-PbO 2 active layer grew along the advantageous (200) crystal plane and formed more point defects in the crystal lattice of β-PbO 2 . Thereby, the electron transfer rate at the anode interface was accelerated and the electrocatalytic performance of Ti/β-PbO 2 was significantly improved. To verify the practical application of the improved Ti/Cs-SnO 2 /β-PbO 2 electrode, levofloxacin (LFX) and ciprofloxacin (CIP) were selected as the typical target fluoroquinolones to evaluate the degradation efficiency of Ti/Cs-SnO 2 /β-PbO 2 anode. The removal rate exceeded more than 90% for the single and mixed fluoroquinolones wastewater. Moreover, after 5 times’ recycle, the degradation efficiency of LFX on Ti/Cs-SnO 2 /β-PbO 2 anode still remained over 90%. The potential mechanism of the enhanced electrocatalytic performance of Ti/Cs-SnO 2 /β-PbO 2 and the degradation pathways of fluoroquinolones were also inferred. It’s the first time to enhance the electrocatalytic performance of the Ti/β-PbO 2 anode by introducing monovalent alkali metal (C S ) into the SnO 2 intermediate layer and the proposed Ti/Cs-SnO 2 /β-PbO 2 anode would be a promising candidate to realize the efficient removal of the practical fluoroquinolones antibiotic wastewater.
危险品化学品经营许可证（带存储）