An in-situ strategy to analyze multi-effect catalysis in iron-copper bimetals catalyzed Fenton-like processes

Iron-copper bimetals for Fenton-like catalysis were developed, due to efficient enhancement of catalytic activity by iron-copper synergy. However, deviation exists in mechanism analysis of multi-effect catalysis. In this study, a new in-situ strategy of shielding Fe(II) and Cu(I) from further reaction by trapping agents was developed, for analysis of iron catalysis alone, copper catalysis alone and synergistic effect in bimetallic catalyst systems. Inhibition efficiency and influence of trapping agents on Fe(II)/Cu(I) catalysis were quantitatively evaluated for reliability confirmation and method correction. The possible application scope was identified as pH of 4–6, and this strategy was available for analysis of five different groups of catalysts. The potential superiority and difference of the proposed strategy compared with current ex-situ strategy were also analyzed. The overestimation (12.1%–35.4%) of copper catalysis and biased analysis (0.1%–12.6%) of iron catalysis by ex-situ strategy can be alleviated, thereby improving accuracy for synergistic effect. In summary, this study proposed a new strategy to improve the understanding of iron-copper bimetallic catalysis, which can provide reference for other polymetallic catalysis analysis development.