Unveiling antimony oxides crucial role on electrocatalytic activity evolution of Sb-SnO2 catalysts during organic pollutants oxidation

Sb-SnO 2 is a low-cost and high-efficiency catalyst, but its short service life restricts widespread use. Enhancing its electrochemical stability remains challenging. Herein, we employed a life-cycle assessment to reveal the mechanisms driving the electrocatalytic activity evolution of Sb-SnO 2 . The results demonstrate that Sb is crucial for maintaining electrocatalytic activity and structural stability of Sb-SnO 2 . Sb functions as a ‘sacrificial agent’ to preserve SnO 2 and further retard the structural collapse. It enhances ∙OH yield in SnO 2 through the Sb 5 + /Sb 3+ cycle, whereas its depletion leads to increased electron transfer resistance and deteriorated electronic structures, significantly impairing ∙OH generation. Additionally, underlying mechanisms related to the transformation in ∙OH presence forms and external passivation synergistically impair the electrocatalytic activity. Combining the structure-activity relationship, we propose a strategy for evaluating the catalytic lifetime of Sb-SnO 2 by utilizing a constructed electrochemical activity coefficient to describe catalyst activity decay. This strategy facilitates the cost-effective application of Sb-SnO 2 in wastewater treatment while evading its potential ion leaching risk. These insights offer an innovative approach to characterizing catalyst activity decay.