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The terms biomimetic and bioinspired are very relevant in the field of bioinorganic chemistry and have been widely applied. Although they were defined by the International Organization for Standardization in 2015, these terms have at times been used rather ambiguously in the literature. This may be due to the inherent complexity of bioinorganic systems where, for example, a structural model of an enzyme active site may not replicate its function. Conversely, the function of an enzyme may be reproduced in a system where the structure does not resemble the enzyme’s active site. To address this, we suggest definitions for the terms biomimetic and bioinspired wherein structure and function have been decoupled. With the help of some representative case studies we have outlined the challenges that may arise and make suggestions on how to apply terminology with careful intention.

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 H2O2generation has hardly been investigated in a systematic manner, and it is unknown if their stability is sufficient for H2O2generation in bulk electrolysis. This study answers these questions using the copper-based Cu(tmpa) (tmpa = tris(2-pyridylmethyl)amine) complex. Since the selectivity of H2O2production originates from the relative rates of oxygen and H2O2reduction, we show that substrate availability and catalyst concentration are key descriptors to tune the selectivity. Consequently, we can control the Faradaic efficiency to H2O2(FEH2O2) in bulk electrolysis, and micromolar concentrations of Cu(tmpa) are sufficient for H2O2production with an FEH2O2of more than 50% over 8 h. Additionally, we show that Cu(tmpa) has a great electrochemical stability and is able to generate H2O2in various electrolytes.