Nanozyme Based on Porphyrinic Metal–Organic Framework for Electrocatalytic CO₂ Reduction

Mimicry of natural enzyme systems is an important approach for catalyst design. To create an enzyme-inspired catalyst, it is essential to mimic both the active center and the second coordination sphere. Metal–organic frameworks (MOFs), an emerging class of porous materials, are ideal candidates for heterogeneous catalysts because their versatile building blocks confer a high level of structural tunability, and the chemical environment surrounding the active center can be controlled at the molecular level. Herein, a new 2D porphyrinic MOF, PPF-100, constructed from a nonplanar saddle-distorted porphyrin linker and a Cu paddle-wheel metal node is reported. The strategic introduction of ethyl substituents allows not only to mimic the active center and second coordination sphere but also to increase the catalytic selectivity while completely inhibiting H₂ generation in the CO₂ reduction reaction.