Additive adsorption shifts zinc anode work function to steer crystal orientation

A study published in Nature Chemistry reports that the long-standing explanation for how additives steer this process is incomplete, and it proposes a different rule based on a fundamental electronic property of the metal surface. The work, led by Sijun Wang, Le Yu and Chaoji Chen together with colleagues including Won-Yeong Kim, Yongming Sun and Sang-Young Lee, examined 29 additives and combined extensive experiments with atomistic computations to find out why some additives produce zinc crystals with a strongly preferred orientation while others do not.

For decades, researchers assumed that additives control the orientation of zinc electrocrystallization by adsorbing selectively onto particular crystal facets, thereby promoting growth on the faces they favour. The authors note that this conventional wisdom is increasingly challenged by mounting literature counterexamples, cases in which the simple selective-adsorption picture fails to predict what happens. To resolve the contradiction, the team carried out case-by-case experimental and computational investigations across a large panel of additives, mapping how each molecule interacts with different atomic arrangements on the zinc surface.

The central result is that the decisive factor is not selective adsorption itself but the change in work function that occurs when additives adsorb in a facet-dependent manner. When an additive molecule sits on a given facet, it alters that facet’s work function, and the study confirms that this variation is the governing factor for the crystallographic orientation of the deposited zinc. Using this criterion, the researchers achieved a prediction accuracy of 93.1 percent across their additive set, a figure that suggests the work-function shift can serve as a fundamental screening rule for choosing additives that favour a desired zinc texture.

The practical importance of this rule became clear when the team examined the electrochemical consequences of different orientations. Zinc electrocrystallization with a preferred (100) orientation delivered outstanding cyclability even under harsh conditions, sustaining high current densities of up to 20 milliamperes per square centimetre and deep cycling with a depth of discharge exceeding 85 percent. This finding challenges the consensus that the (002) orientation is the optimal one for practical zinc anodes, a belief that has guided additive design in aqueous zinc battery research for years.

The study combined four lines of evidence. Morphological and crystallographic evolution of zinc electrocrystallization was tracked under additive regulation, mechanistic investigations probed how the additives drive texture evolution, and comparative electrochemical tests were run in symmetric zinc-zinc cells, in zinc-copper cells and in practical full cells. Schematics presented in the paper contrast the traditional facet-adsorption framework with the work-function framework, showing how the same experimental observations can be interpreted within two very different mechanistic pictures.

By identifying work-function modulation through facet-dependent adsorption as the governing factor for zinc orientation, and by showing that a non-(002) texture can outperform the presumed optimum under severe conditions, the study offers both a mechanistic correction and a practical design principle.

Subject of Research: Work-function changes caused by facet-dependent additive adsorption govern the crystallographic orientation of zinc electrocrystallization in aqueous zinc battery anodes.

Article Title: Facet-dependent molecular adsorption modulates zinc anode work function for the favourable orientation of zinc electrocrystallization

Article References: Wang, S., Yu, L., Huang, J., Cai, Z., Chen, L., Lu, Z., Kim, W.-Y., Sun, Y., Lee, S.-Y., & Chen, C. (2026). Facet-dependent molecular adsorption modulates zinc anode work function for the favourable orientation of zinc electrocrystallization. Nature Chemistry. https://doi.org/10.1038/s41557-026-02291-7

Image Credits: AI Generated

DOI: 10.1038/s41557-026-02291-7

Keywords: zinc anodes, aqueous zinc batteries, electrocrystallization, work function, additives, crystal orientation, dendrites, battery cycling, Nature Chemistry, electrochemistry, Facet-dependent, molecular