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Abstract Alternating current (AC) and pulsed electrolysis are gaining traction in electro(organic) synthesis due to their advantageous characteristics. We employed AC electrolysis in electrochemically mediated Atom Transfer Radical Polymerization (eATRP) to facilitate the regeneration of the activator Cu^Icomplex on Cu⁰electrodes. Additionally, Cu⁰served as a slow supplemental activator and reducing agent (SARA ATRP), enabling the activation of alkyl halides and the regeneration of the Cu^Iactivator through a comproportionation reaction. We harnessed the distinct properties of Cu⁰dual regeneration, both chemical and electrochemical, by employing sinusoidal, triangular, and square‐wave AC electrolysis alongside some of the most active ATRP catalysts available. Compared to linear waveform (DC electrolysis) or SARA ATRP (without electrolysis), pulsed and AC electrolysis facilitated slightly faster and more controlled polymerizations of acrylates. The same AC electrolysis conditions could successfully polymerize eleven different monomers across different mediums, from water to bulk. Moreover, it proved effective across a spectrum of catalyst activity, from low‐activity Cu/2,2‐bipyridine to highly active Cu complexes with substituted tripodal amine ligands. Chain extension experiments confirmed the high chain‐end fidelity of the produced polymers, yielding functional and high molecular‐weight block copolymers. SEM analysis indicated the robustness of the Cu⁰electrodes, sustaining at least 15 consecutive polymerizations. 

In Atom Transfer Radical Polymerization (ATRP), Cu 0 acts as a supplemental activator and reducing agent (SARA ATRP) by activating alkyl halides and (re)generating the Cu I activator through a comproportionation reaction, respectively. Cu 0 is also an unexplored, exciting metal that can act as a cathode in electrochemically mediated ATRP ( e ATRP). Contrary to conventional inert electrodes, a Cu cathode can trigger a dual catalyst regeneration, simultaneously driven by electrochemistry and comproportionation, if a free ligand is present in solution. The dual regeneration explored herein allowed for introducing the concept of pulsed galvanostatic electrolysis (PGE) in e ATRP. During a PGE, the process alternates between a period of constant current electrolysis and a period with no applied current in which polymerization continues via SARA ATRP. The introduction of no electrolysis periods without compromising the overall polymerization rate and control is very attractive, if large current densities are needed. Moreover, it permits a drastic charge saving, which is of unique value for a future scale-up, as electrochemistry coupled to SARA ATRP saves energy, and shortens the equipment usage.