Ce/Zr-MOF with Dual Cycle Synergistic Catalysis Pathway Enabling Enhanced Peroxidase-like Performance for Wearable Hydrogel Patch Visualization Sensing Platform

Engineering the activity of enzyme-like catalysts should be a top priority to make them superior substitutes for natural enzymes. Herein, a Ce/Zr bimetal–organic framework (Ce/Zr-MOF) was designed and synthesized by a one-pot hydrothermal method, which has enhanced performance in mimicking peroxidase (POD) than its single-metal counterparts. To further comprehend the mechanism of activity enhancement, the role of the bimetallic synergistic catalysis process in H2O2 decomposition and reactive oxygen species formation was elucidated, and the possible dual cycle synergistic catalysis pathway of bimetallic catalysis is proposed for the first time. The enhanced POD-like activity mainly depends on the introduction of Ce, which improved the conductivity and electron-transfer capability of Ce/Zr-MOF and promoted the generation of •OH. Integrated with a hydrogel substrate, a wearable all-solid-state H2O2 sensor for early diagnosis of plant health was produced. The detection limit can be as low as 3.3 μM, which is lower than that of some instrument-based colorimetric methods and has great potential in the development of visualized sensing applications. The concept of dual cycle synergistic catalysis pathway we proposed not only deepens the comprehension regarding sensing and catalytic mechanisms but also provides novel perspectives into the design of enzyme-like catalysts for extensive usage.