Benchmarking pH-field coupled microkinetic modeling against oxygen reduction in large-scale Fe–azaphthalocyanine catalysts

Abstract

calculations and electric field-pH coupled simulations to analyze the pH-dependent ORR performance of carbon-supported Fe-AzPcs with varying surrounding functional groups. In particular, this study incorporates large molecular structures with complex long-chain "dancing patterns", each featuring >650 atoms, to analyze their performance in the ORR. Comparison with experimental ORR data shows that pH-field coupled microkinetic modeling closely matches the observed ORR efficiency at various pH levels in Fe-AzPc catalysts. Our results also indicate that assessing charge transfer at the Fe-site, where the Fe atom typically loses around 1.3 electrons, could be a practical approach for screening appropriate surrounding functional groups for the ORR. This study provides a direct benchmarking analysis for the microkinetic model to identify effective M-N-C catalysts for the ORR under various pH conditions.