ABSTRACT Aqueous zinc‐ion batteries are plagued by anode challenges such as dendrite growth and corrosion, which stem from intrinsic surface heterogeneity. Although constructing a homogeneous interfacial layer is a promising strategy, conventional electrolyte additives often suffer from incomplete or unstable coverage. Here, we evaluated thiol‐containing 2‐mercaptopyridine (MP) as a potential additive because of its strong coordination capability. However, it unexpectedly exacerbated localized dendrite formation, revealing strong yet uneven adsorption. Enlightened by this, we constructed a uniform MP‐based molecular monolayer through a tailored solution immersion process, thereby converting a detrimental effect into a superior protective function. This engineered interface, anchored through dual active sites (thiol and pyridine nitrogen), enables ultrafast and homogeneous zinc adsorption and deposition. Experimental and theoretical results confirm that the monolayer modulates surface charge distribution, suppresses tip‐enhanced electric fields, and guides uniform ion flux. Consequently, the symmetric cell achieves exceptional cycling stability of 2100 h at 1 mA cm −2 and 1 mAh cm −2 . The Zn||Cu cell cycles stably for over 1100 h with a 99.35% average Coulombic efficiency, whereas full cells show markedly enhanced capacity retention. This work demonstrates a rational interface design by turning an initial failure into a functional strategy.
Huang et al. (Fri,) studied this question.