, then large ∆𝐺 ∘′ changes (e.g., 0.5 eV) could change kET by a factor of 10-100. It is even possible that ∆𝐺 ∘′ changes sign if the VB/CB edge moves above/below 𝐸 ∘′ . This means the (photo)electrocatalytic reaction could transition from being spontaneous in one potential regime to non-spontaneous in another. Note, our study focused only on BGR effects caused by the applied potential. For light-driven reactions in a photoelectrosynthetic cell, the band edge movement will be driven by the applied bias and the photogenerated carrier population , further complicating the interfacial energetics. One could envision leveraging this kinetic or thermodynamic information to design an "electrochemical switch" for a desired reaction.