A study explores how an external electric field can enhance the oxygen evolution reaction (OER) using alpha-manganese dioxide (α-MnO₂) as a model catalyst. The research reveals that pre-equilibrium proton-coupled redox transitions can adjust the energy profile of OER, enabling in-situ enhancement of proton coupling through an external electric field. Using α-MnO₂ single-nanowire devices, the study shows a fourfold increase in OER current density at 1.7 V versus reversible hydrogen electrode. A proof-of-principle external electric field-assisted flow cell for water splitting demonstrates a 34% increase in current density and a 44.7 mW/cm² increase in net output power. These findings indicate a deeper understanding of the role of proton-incorporated redox transitions and develop practical approaches for high-efficiency electrocatalysis. OER is a key reaction in many biological and chemical processes, including artificial photosynthesis, electrocatalytic water splitting, and rechargeable metal-air batteries. Understanding OER processes and developing efficient catalysts are crucial for advancing these technologies. Inspired by enzyme catalysis, researchers have synthesized catalysts mimicking enzyme structures. The study highlights the importance of the Mn₄CaOₓ cluster in Photosystem II for oxygen evolution. α-MnO₂, with its low cost and structural similarity to enzymes, is considered a promising biomimetic catalyst for OER. The study investigates the structural and functional role of the μ-oxo-di-manganese structure and protons in the oxygen evolution process. In situ Raman and EXAFS spectroscopy reveal that the di-μ-oxo structure in α-MnO₂ is similar to the Mn⁴-O-Mn³-HₓO motif in the Mn₄CaOₓ complex. The study shows that the proton-coupled electron transfer (PCET) process leads to more favorable energetics compared to sequential pathways. The PCET process allows for a rapid redox transition without significant overpotential, ensuring high activity in biological systems. The study demonstrates that an external electric field can enhance the deprotonation and proton coupling for high-efficiency electrocatalysis. The α-MnO₂ nanowire device shows an exceptionally low overpotential of 360 mV (at 100 mA/cm²), significantly better than without an electric field. The study also demonstrates that the external electric field can enhance the overall water splitting process in a centimetre-sized electrolyser, increasing the current density by 34% using the MnO₂ film electrode. The study shows that the external electric field can regulate the proton-electron transfer process, enhancing the OER performance of α-MnO₂. The results indicate that the electric field changes the surface ligand field environment and controllably influences the redox transition of MnO₂. The study also demonstrates that theA study explores how an external electric field can enhance the oxygen evolution reaction (OER) using alpha-manganese dioxide (α-MnO₂) as a model catalyst. The research reveals that pre-equilibrium proton-coupled redox transitions can adjust the energy profile of OER, enabling in-situ enhancement of proton coupling through an external electric field. Using α-MnO₂ single-nanowire devices, the study shows a fourfold increase in OER current density at 1.7 V versus reversible hydrogen electrode. A proof-of-principle external electric field-assisted flow cell for water splitting demonstrates a 34% increase in current density and a 44.7 mW/cm² increase in net output power. These findings indicate a deeper understanding of the role of proton-incorporated redox transitions and develop practical approaches for high-efficiency electrocatalysis. OER is a key reaction in many biological and chemical processes, including artificial photosynthesis, electrocatalytic water splitting, and rechargeable metal-air batteries. Understanding OER processes and developing efficient catalysts are crucial for advancing these technologies. Inspired by enzyme catalysis, researchers have synthesized catalysts mimicking enzyme structures. The study highlights the importance of the Mn₄CaOₓ cluster in Photosystem II for oxygen evolution. α-MnO₂, with its low cost and structural similarity to enzymes, is considered a promising biomimetic catalyst for OER. The study investigates the structural and functional role of the μ-oxo-di-manganese structure and protons in the oxygen evolution process. In situ Raman and EXAFS spectroscopy reveal that the di-μ-oxo structure in α-MnO₂ is similar to the Mn⁴-O-Mn³-HₓO motif in the Mn₄CaOₓ complex. The study shows that the proton-coupled electron transfer (PCET) process leads to more favorable energetics compared to sequential pathways. The PCET process allows for a rapid redox transition without significant overpotential, ensuring high activity in biological systems. The study demonstrates that an external electric field can enhance the deprotonation and proton coupling for high-efficiency electrocatalysis. The α-MnO₂ nanowire device shows an exceptionally low overpotential of 360 mV (at 100 mA/cm²), significantly better than without an electric field. The study also demonstrates that the external electric field can enhance the overall water splitting process in a centimetre-sized electrolyser, increasing the current density by 34% using the MnO₂ film electrode. The study shows that the external electric field can regulate the proton-electron transfer process, enhancing the OER performance of α-MnO₂. The results indicate that the electric field changes the surface ligand field environment and controllably influences the redox transition of MnO₂. The study also demonstrates that the