Platinum alloy nanoparticles provide a technologically important catalyst for oxygen reduction reactions. The interactions of these nanoparticles with water under electrochemical conditions can lead to roughening and oxidation of the surface, leaching non-noble alloy components, and dissolution of platinum. The behavior of these nanoparticles is the complex result of chemical ordering within the nanoparticle, surface structure and composition, nanoparticle size, and the electrochemical conditions they are subjected to. Here, the vulnerability of alloy catalysts is explored with classical molecular dynamics using 3rd generation charge-optimized many-body potentials (COMB3). Electrochemical conditions are created by simulating an applied voltage using the electrode COMB (eCOMB) method. By offsetting the electronegativity of the electrode atoms, a new imbalanced set of charge equations of motion are generated. This method allows the atomistic simulation of water splitting, ion diffusion through an electrolyte, and electrochemically driven surface oxidation, allowing insights into the degradation of structured Pt alloy nanoparticles.