Population dynamics of driven autocatalytic reactive mixture

A reactive mixture undergoes thermal fluctuation and reacts with the reservoir when chemically driven. We apply the Fokker-Planck equation consistent with statistical physics to describe the ensemble dynamics. We illustrate the effect of autocatalysis on the ensemble dynamics by comparing systems with identical thermodynamics yet different reaction kinetics. Fictitious phase separation may occur in autocatalytic systems. Reversely, autoinhibition may suppress phase separation, leading to dynamic phase behavior entirely different from thermodynamic equilibrium.

We also present examples found in electrochemical systems such as lithium iron phosphate and LiNi_1/3Mn_1/3Co_1/3O₂ (NMC). XRD, STXM and other analytical techniques have revealed intriguing asymmetric autocatalytic or autoinhibitory reaction kinetics and the corresponding phase transition behavior during charge and discharge. As an application, we obtain the inherent reaction kinetics from XRD and electrochemical experiments performed on NMC and demonstrate the agreement between experiments and simulation.