Promoting the electrocatalytic performance of PbO2 nanocrystals via incorporation of Y2O3 nanoparticles: Degradation application and electrocatalytic mechanism.

• A novel PbO 2 /Y 2 O 3 nano-composite anode with hybrid interfaces was prepared. • Incorporating Y 2 O 3 optimized the crystal size and adsorbed oxygen of PbO 2. • Obtained the significantly improved degradation efficiency to malachite green. • The electrocatalytic degradation mechanism of PbO 2 /Y 2 O 3 anode was revealed. Underlying the electrocatalytic mechanism has profound influences on designing novel efficient electrocatalytic interfaces and improving the efficiency of electrocatalytic degradation. In this study, a novel PbO 2 /Y 2 O 3 nano-composite anode with hybrid interface was successfully prepared to investigate the electrocatalytic oxidation of malachite green (MG). The comprehensively analyzed XRD and XPS results confirmed that the partial incorporation of Y 2 O 3 nanoparticles reduced the crystal size of PbO 2 and increased the adsorption of hydroxyl oxygen (O ads). The bipotential step chronoamperometry (BSCP) curve suggested that PbO 2 /Y 2 O 3 anode possessed larger diffusion coefficients (D) and catalytic rate constants (K cat). In addition, the incorporated Y 2 O 3 nanoparticles promoted the electrocatalytic activity at the anode interface and enhanced the electron transfer as well as accelerated the generation of reactive oxygen species (ROS), which afford the PbO 2 /Y 2 O 3 anode high removal efficiency of MG and total organic carbon (TOC) with low energy consumption under the optimum conditions. Moreover, the electrocatalytic degradation mechanism and possible electrocatalytic mineralization pathway of MG on PbO 2 /Y 2 O 3 anode were also discussed in detail, which provides a reference for the material science and environmental governance in the future. Image, graphical abstract [ABSTRACT FROM AUTHOR]