Hydrogen peroxide (H₂O₂) generation via electrochemical oxygen reduction is a sustainable production method for this bulk chemical. However, the selectivity of molecular catalysts for electrochemical H₂O₂ generation has hardly been investigated in a systematic manner, and it is unknown if their stability is sufficient for H₂O₂ generation in bulk electrolysis. This study answers these questions using the copper-based Cu(tmpa) (tmpa = tris(2-pyridylmethyl)amine) complex. Since the selectivity of H₂O₂ production originates from the relative rates of oxygen and H₂O₂ reduction, we show that substrate availability and catalyst concentration are key descriptors to tune the selectivity. Consequently, we can control the Faradaic efficiency to H₂O₂ (FE_H2O2) in bulk electrolysis, and micromolar concentrations of Cu(tmpa) are sufficient for H₂O₂ production with an FE_H2O2 of more than 50% over 8 h. Additionally, we show that Cu(tmpa) has a great electrochemical stability and is able to generate H₂O₂ in various electrolytes.

通过电化学氧还原产生过氧化氢 (H ₂ O ₂ ) 是这种大宗化学品的可持续生产方法。然而，分子催化剂对电化学H ₂ O ₂生成的选择性几乎没有系统地研究，并且尚不清楚它们的稳定性是否足以在本体电解中生成H ₂ O ₂ 。本研究使用铜基 Cu(tmpa)（tmpa = 三（2-吡啶基甲基）胺）络合物回答了这些问题。由于H ₂ O ₂生产的选择性源自氧气和H ₂ O ₂还原的相对速率，我们表明底物可用性和催化剂浓度是调节选择性的关键描述符。因此，我们可以控制本体电解中H ₂ O ₂ (FE _H2O2 )的法拉第效率，微摩尔浓度的Cu(tmpa)足以在8小时内生产H ₂ O ₂ ，​​FE _H2O2超过50%。此外，我们还发现Cu(tmpa)具有良好的电化学稳定性，能够在各种电解质中产生H ₂ O ₂ 。