Programming Ion Transport in Phenyl‐Bridged Graphene Layers via Delocalization‐Catalyzed Decoupling

Abstract

ABSTRACT Graphene nanomaterials have shown extraordinary potential in capacitive deionization, but their actual performance often falls far short of theoretical predictions due to limited ion diffusion caused by narrow interlayer spacing. More importantly, the relationship between interlayer spacing and desalination efficiency remains unclear, hindering rational design. Here, we develop a delocalization‐catalyzed decoupling strategy that simultaneously regulates the interlayer structure and local electronic environment of phenyl‐bridged holey reduced graphene oxide. In this concept, phenyl bridging induces interlayer expansion and weakens direct graphene–graphene coupling, whereas the associated phenyl–graphene conjugation gives rise to interfacial charge redistribution and electron delocalization that facilitate charge and ion transport within the decoupled layered architecture. Crucially, we establish a semi‐quantitative correlation framework connecting interlayer structure, local electronic environment, local ion distribution, and macroscopic electrochemical behavior. This mechanistic insight advances our understanding of the structure‐activity relationship in layered materials. The electrode exhibited an ultra‐high desalination capacity of 80.6 mg g − 1 , an excellent adsorption rate of 16.12 mg g − 1 min − 1 , and outstanding stability with a capacity retention rate of 93.6% after 450 cycles, which exceeds previously reported. This study provides a semi‐quantitative correlation framework and methodological guidance for the rational design of 2D materials in ion capture and transport.