Dynamic stretching beyond electron transfer in a homointerpenetrated metal‒organic framework for enhanced Fenton-like reactions.

While extensive efforts have been devoted to enhancing electron transfer efficiency through metal valence cycling in heterogeneous Fenton-like reactions, the potential catalytic improvement induced by dynamic structural stretching remain unexplored. Here, we introduce a homointerpenetrated Fe-based metal‒organic framework (BUC-95) featuring a dynamic stretchable structure that significantly boosts the heterogeneous Fenton-like catalytic performance. BUC-95's unique stretchable structure achieved effective peroxydisulfate activation for degrading various micropollutants via Fe(IV) = O species, facilitated by a reduced energy barrier for Fe(IV) = O formation through modulation of the electron density at Fe sites. DFT calculations suggest that, compared with the isostructural analogue with hydrogen bond-restricted stretching, the flexible dynamic stretching in BUC-95 overcomes the inherent electron transfer limitations from Fe sites to peroxydisulfate, enhancing the ofloxacin degradation performance. Practically, BUC-95 demonstrated effective continuous-flow degradation and detoxification of micropollutants. This work establishes dynamic stretching as a crucial design principle for advancing environmental remediation materials and technologies.