近日，南开大学章炜团队报道了铜上的镀锌通过电容性双电层的击穿进行。相关论文于2025年12月9日发表在《美国化学会志》上。

固液界面处的双电层主导着从电镀到催化的众多电化学过程，但其原子尺度动力学机制仍不明确。

研究组通过原位原子分辨率透射电镜，直接观察了离子液体电解质中铜表面锌电镀过程中双电层的形成、生长与坍塌。在恒电流条件下，双电层呈现为致密的无定形层，并通过电荷积累逐渐增厚；基底材料的动态表面侵蚀释放出表面原子，这些原子在双电层内成核形成瞬态金属纳米粒子。这些粒子的长大导致局部电容层短路，引发突然的介电击穿、热量产生及合金沉积。反复的生长-击穿循环（240–520秒）形成了约2纳米的铜/锌合金层，其活化自由能约为86 kJ·mol^-1。

引人注目的是，黄铜纳米粒子在室温下即可自发形成，而块体材料合成通常需要约1000°C的高温，这反映了纳米尺度物种的巨大界面能。这种击穿驱动的机制将电镀重新定义为一种非连续、具有化学反应活性且静电不稳定的过程，为电镀薄膜中常见的粗糙形貌提供了统一解释。更广泛而言，该研究表明化学活性双电层的介电击穿是一种普遍现象，与电镀、储能、催化及其他界面转化过程密切相关。

附：英文原文

Title: Zinc Plating on Copper Proceeds via Breakdown of a Capacitive Electric Double Layer

Author: Haoxiang Sun, Shulin Ding, Jinkai Zhang, Yujie Chen, Xinyao Wu, Zhao Zhang, Tong Zhou, Zhenhua Yan, Kai Zhang, Qing Zhao, Wei Xie, Ke Yang, Guang Feng, Eiichi Nakamura, Jun Chen, Wei Zhang

Issue&Volume: December 9, 2025

Abstract: The electric double layer (EDL) at solid–liquid interfaces governs electrochemical processes from plating to catalysis, yet its atomistic dynamics remain poorly defined. Using operando atomic-resolution transmission electron microscopy, we directly visualize EDL formation, growth, and collapse during zinc electroplating on copper in an ionic liquid electrolyte. Under galvanostatic conditions, the EDL appears as a dense amorphous layer that grows via charge accumulation, and dynamic surface erosion of the substrate releases surface atoms that nucleate transient metallic nanoparticles within the EDL. Enlargement of these particles locally short-circuits the capacitive layer, leading to abrupt dielectric breakdown, heat generation, and alloy deposition. Recurrent growth–breakdown cycles (240–520 s) produce ～2 nm Cu/Zn alloy layers, with an activation free energy of ～86 kJ mol–1. Strikingly, brass nanoparticles form spontaneously at room temperature despite requiring ～1000 °C in bulk, reflecting the large interfacial energy of nanoscale species. This breakdown-driven mechanism reframes electroplating as a discontinuous, chemically reactive, and electrostatically unstable process, providing a unifying explanation for the rough morphologies often observed in plated films. More broadly, our findings suggest that the dielectric breakdown of chemically active EDLs is a general phenomenon relevant to plating, energy storage, catalysis, and other interfacial transformations.

DOI: 10.1021/jacs.5c17948

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.5c17948