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This perspective provides a brief overview on the role of isomerism of secondary‐sphere functionality in molecular electrocatalysis, without which there exists a clear knowledge‐gap in defining a molecule's structure‐activity relation. The discussion unfolds how isomerism of the functionality triggers short‐range interactions in the molecule leading to unprecedented events in electrocatalysis. This perspective highlights that the isomerism of substituents makes an independent contribution to electrocatalysis over its nature and for exploiting the maximum potential of the molecule in electrocatalysis, nature of the substituent as well as its isomerism should be given consideration.

The state-of-the-art battery performance is often limited by the cathode, and consequently, expanding the storage metrics often requires a heavy cathode. Since charge is stored within the bulk of the electrodes in most batteries, energy/power trade-off is one of their classical challenges, and alternative cell chemistries that avoid these drawbacks are highly sought after. We demonstrate an ultra-high-capacity metal-ion battery comprising an acidic aqueous electrolyte with suspended magnetite particles and a hexacyanometallate-based insertion cathode. During discharge, the hexacyanometallate is reversibly reduced, and its original redox state is restored during intermittent periods by wirelessly charging with magnetite particles. Recovery involves sacrificial surface redox of the Fe 3+ / Fe 2+ couple in magnetite particles with the formation of water and re-oxidation of hexacyanometallate. The structural flexibility of the magnetite particles with respect to their oxidation states leads to a high cumulative capacity battery, which offers opportunities for fast and remote charging with minimal power losses.

Integrating bifunctional applications in a single electrochemical device is highly desirable as it potentially enhances the electrical efficiency. We herein report a hybrid alkali−salt−acid electrochemical cell (h-ASAEC) that is capable of simultaneously implementing electrodesalination and H 2 generation in an electricity-efficient manner by lowering the electrical energy input required for electrodesalination and H 2 generation, thanks to the electrical driving force of neutralization energy by virtue of the pH gradients in the three-compartment cell. The h-ASAEC at an electrolytic current density of 40 mA/cm 2 performs electrodesalination with minimal parasitic chemistry while generating ∼33 mL/h of H 2 at a terminal voltage of ∼1 V, which is only half of the voltage required in a symmetric configuration. Contrary to the conventional desalination process, the low-voltage electrodesalination in the h-ASAEC noticeably improves the electrical energy efficiency and prevents competitive parasitic chemistry.