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Rechargeable aqueous zinc-ion batteries are practically plagued by the short lifespan and low Coulombic efficiency (CE) of Zn anodes resulting from random dendrite deposition and parasitic reactions. Herein, the host-guest chemistry of cucurbituril additive with Zn 2+ to achieve longstanding Zn anodes is manipulated. The macrocyclic molecule of cucurbit[5]uril (CB[5]) is delicately designed to reconstruct both the CB[5]-adsorbed electric-double layer (EDL) structure at the Zn interface and the hydrated sheath of Zn 2+ ions. Especially benefiting from the desirable carbonyl rims and suitable hydrophobic cavities, the CB[5] has a strong host-guest interaction with Zn 2+ ions, which exclusively permits rapid Zn 2+ flux across the EDL interface but retards the H 2 O radicals and SO 4 2- . Accordingly, such a unique particle redistributor warrants long-lasting dendrite-free deposition by homogenizing Zn nucleation/growth and significantly improved CE by inhibiting side reactions. The Zn anode can deliver superior reversibility in CB[5]-containing electrolyte with a ninefold increase of cycle lifetime and an elevated CE of 99.7% under harsh test conditions (10 mA cm -2 /10 mA h cm -2 ). The work opens a new avenue from the perspective of host-guest chemistry to propel the development of rechargeable Zn metal batteries and beyond., (© 2023 Wiley‐VCH GmbH.)

Inspired by nature, artificial hydrogen bond-based anion receptors have been developed to achieve high anion selectivity; however, their binding affinity is usually low. The potency of these receptors is usually increased by the introduction of aryl substituents, which withdraw electrons from their binding site through the resonance effect. Here, we show that the polarization of the C(sp 3 )-H binding site of bambusuril receptors, and thus their potency to bind anions, can be modulated by the inductive effect. The presence of electron-withdrawing groups on benzyl substituents of bambusurils significantly increases their binding affinities to halides, resulting in the strongest iodide receptor reported to date with an association constant greater than 10 13  M -1 in acetonitrile. A Hammett plot showed that while the bambusuril affinity toward halides linearly increases with the electron-withdrawing power of their substituents, their binding selectivity remains essentially unchanged., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)