Fig. 2: Overview of ¹³C signal evolution during the chronoamperometry (CA) stage.

Time evolution of voltage and current density as well as the corresponding ¹³C NMR signals at B₀ = 14.1 T of \({{{{{{{{{\rm{HCO}}}}}}}}}_{3}}^{-}\) and CO₂ during CA with a constant voltage of -1.1 V. A new peak emerges for the \({{{{{{{{{\rm{HCO}}}}}}}}}_{3}}^{-}\) signal.