At the electrochemical potentials of relevance to NO3RR, most metals are below their potential of zero charge (pzc) and thus have negative surface charge . Electrostatically this acts against the adsorption of the nitrate anion . The nature of cations in solution therefore impacts the NO3RR performance. The involvement of 9 H + for NH3 production also gives pH-dependence to the reversible potential and resultant overpotential, highlighting the importance of measuring and/or controlling the local pH. Historical studies of cation and anion effects are convoluted with pH changes from unbuffered neutral electrolytes, differences in proton donor strengths of hydrated cations compared to water, and local electric fields . Though systematic investigations are lacking, NO3RR ion effects can likely impact not only rate but also FE and selectivity, similar to CO2RR.