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The performance of electrocatalysts is critical for renewable energy technologies. While the electrocatalytic activity can be modulated through structural and compositional engineering following the Sabatier principle, the insufficiently explored catalyst-electrolyte interface is promising to promote microkinetic processes such as physisorption and desorption. By combining experimental designs and molecular dynamics simulations with explicit solvent in high accuracy, we demonstrated that dimethylformamide can work as an effective surface molecular pump to facilitate the entrapment of oxygen and outflux of water. Dimethylformamide disrupts the interfacial network of hydrogen bonds, leading to enhanced activity of the oxygen reduction reaction by a factor of 2 to 3. This strategy works generally for platinum-alloy catalysts, and we introduce an optimal model PtCuNi catalyst with an unprecedented specific activity of 21.8 ± 2.1 mA/cm²at 0.9 V versus the reversible hydrogen electrode, nearly double the previous record, and an ultrahigh mass activity of 10.7 ± 1.1 A/mg_Pt. 

Ru decorated Ag nanoparticles are designed as highly effective bifunctional electrocatalysts for hydrazine oxidation and hydrogen evolution reactions, enabling a hydrazine assisted water electrolyser with greatly increased current density. 

Abstract Aldehyde‐assisted water electrolysis offers an attractive pathway for energy‐saving bipolar hydrogen production with combined faradaic efficiency (FE) of 200% while converting formaldehyde into value‐added formate. Herein we report the design and synthesis of noble metal‐free Cu₆Sn₅alloy as a highly effective electrocatalyst for formaldehyde electro‐oxidative dehydrogenation, demonstrating a geometric current density of 915 ± 46 mA cm⁻²at 0.4 V versus reversible hydrogen electrode, outperforming many noble metal electrocatalysts reported previously. The formaldehyde‐assisted water electrolyzer delivers 100 mA cm⁻²at a low cell voltage of 0.124 V, and a current density of 486 ± 20 mA cm⁻²at a cell voltage of 0.6 V without any iR compensation and exhibits nearly 200% faradaic efficiency for bipolar hydrogen production at 100 mA cm⁻²in 88 h long‐term operation. Density functional theory calculations further confirm the notably lowered barriers for dehydrogenation and Tafel steps on the Cu₆Sn₅ surface compared to Cu, underscoring its potential as a highly active catalyst. 

Abstract Hydrazine‐assisted water electrolysis offers a feasible path for low‐voltage green hydrogen production. Herein, the design and synthesis of ultrathin RhRu_0.5‐alloy wavy nanowires as bifunctional electrocatalysts for both the anodic hydrazine oxidation reaction (HzOR) and the cathodic hydrogen evolution reaction (HER) is reported. It is shown that the RhRu_0.5‐alloy wavy nanowires can achieve complete electrooxidation of hydrazine with a low overpotential and high mass activity, as well as improved performance for the HER. The resulting RhRu_0.5bifunctional electrocatalysts enable, high performance hydrazine‐assisted water electrolysis delivering a current density of 100 mA cm⁻²at an ultralow cell voltage of 54 mV and a high current density of 853 mA cm⁻²at a cell voltage of 0.6 V. The RhRu_0.5 electrocatalysts further demonstrate a stable operation at a high current density of 100 mA cm⁻²for 80 hours of testing period with little irreversible degradation. The overall performance greatly exceeds that of the previously reported hydrazine‐assisted water electrolyzers, offering a pathway for efficiently converting hazardous hydrazine into molecular hydrogen.