All-atom XL-BOMD simulations show oxygen reduction on nitrogen-doped graphene switching between inner- and outer-sphere mechanisms with applied bias
Using DFTB-based shadow-potential extended Lagrangian Born-Oppenheimer molecular dynamics (XL-BOMD) with explicit water, the authors simulated the oxygen reduction reaction (ORR) on nitrogen-doped graphene (NG) and introduced an electrode-biasing scheme to tune the reaction driving force, observing a solvent-mediated outer-sphere mechanism at higher applied biases (0 to 3.0 eV) and an inner-sphere mechanism involving O2 adsorption at lower biases (-1.25 to -0.25 eV), with kinetics that differ from Butler-Volmer and Marcus-Hush-Chidsey descriptions.