Reply to Correspondence on "Confinement of Polyiodides by Dual-Functional Tetrazine Cathodes in Zn-I₂ Batteries"

In a correspondence related to our previous publication in Angewandte Chemie, Bianchi, Melguizo, et al. (B.M.) commented on the mechanistic interpretation and experimental framework underlying the interaction between 3,6-bis(2-morpholinoethyl)-1,2,4,5-tetrazine (BMT) and I₃ ^- in Zn-I₂ batteries. In this reply, we show that the central findings and mechanistic interpretation of our work remain valid. First, B.M. should recognize the fundamental distinction between bulk solution chemistry and the reactions occurring at the electrochemical interface. It is critical to acknowledge that chemical reactions involving identical reactants may proceed through entirely different pathways under different physicochemical conditions-a principle that is particularly significant for electrochemistry. In Zn-I₂ batteries, the cathodic electrochemical double layers (EDLs) constitute a highly polarized, spatially confined, and locally alkaline microenvironment. The 1:1 first-step association constant reflects the rapid complexation kinetics of nonprotonated BMT toward I₃ ^-, highlighting its effectiveness in anchoring triiodide species at the cathode. Importantly, this value does not imply exclusive 1:1 complex formation, and it remains fully consistent with the 1:2 coordination stoichiometry revealed by the Job's plot analysis. Furthermore, well-converged density functional theory calculations results are fully consistent with various experimental evidence, including in situ spectroscopic, in situ electrochemical measurements, and UV-vis titration experiments in chloroform. Accordingly, the nonprotonated BMT-I₃ ^- coordination mechanism proposed for Zn-I₂ batteries is robust and internally consistent. In contrast, the protonated BMT-I₃ ^- coordination studies reported by B.M. suffer from serious scientific/technical flaws, owing to interference from competing anions and the use of ill-defined, strongly acidic solutions. Such experimental environments are fundamentally different from the cathodic EDL in Zn-I₂ batteries. Nevertheless, to appropriately acknowledge prior contributions, multiple studies by B.M. are cited in both the Introduction and the Supporting Information. These citations fully comply with academic standards. This reply therefore clarifies the BMT-I₃ ^- coordination mechanism in electrochemistry, reaffirms the validity of our conclusions, and underscores the decisive role of the EDL microenvironment in governing cathodic reactions.