Coordinated P Atoms Promote Bifunctional Activity for ORR and HER in Atomically Dispersed Fe‐N _x Sites

ABSTRACT In this study, we report the design and synthesis of a bifunctional Fe‐N‐P@TDC electrocatalyst derived from renewable precursors, tannin and phytic acid. The catalyst was prepared through a mechanochemical reaction of these precursors with urea and FeCl 3 as nitrogen (N) and iron (Fe) precursors, respectively, followed by simple pyrolysis at 900°C. The innovative integration of phosphorus (P) atoms coordinated to Fe‐N x single‐atom sites creates a unique electronic environment that enhances catalytic activity for both ORR and HER. Density Functional Theory (DFT) calculations reveal that FeN 2 P 2 and FeNP 3 configurations are the most active sites, showing synergistic effects of P coordination in weakening intermediate adsorption energies and promoting reaction kinetics. The Fe‐N‐P@TDC catalyst exhibits superior bifunctional activity, with ORR half‐wave potentials and HER overpotentials comparable to commercial Pt/C, but at a fraction of the cost and higher stability. This work demonstrates that fine‐tuning of Fe‐N x coordination with P atoms in sustainable carbon matrices offers a viable route toward efficient, durable, and low‐cost electrocatalysts for clean energy conversion.