Tracking Metal Electrodeposition Dynamics from Nucleation and Growth of a Single Atom to a Crystalline Nanoparticle
Tracking Metal Electrodeposition Dynamics from Nucleation and Growth of a Single Atom to a Crystalline Nanoparticle
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DOI：
10.1021/acsnano.8b04089
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发表时间：
2018-07-01
期刊：
影响因子：
17.1
通讯作者：
Macpherson, Julie V.
中科院分区：
文献类型：
--
作者：
Hussein, Haytham E. M.;Maurer, Reinhard J.;Macpherson, Julie V.
在电沉积中，关键的挑战是获得对纳米结构形态的更好控制。目前，缺乏了解存在有关成核和生长的初始阶段，最终影响所得实体的物理化学性质。使用相同的位置扫描透射电子显微镜（STEM），硼掺杂金刚石（BDD）作为电子透明的TEM基板和电极，我们遵循这个过程，从单个金属原子的形成到结晶金属纳米颗粒，在潜在的脉冲条件下。在这样做的过程中，我们揭示了电化学驱动的原子运输，原子团簇形成，簇进展到纳米粒子的重要性，以及相邻粒子在生长过程中相互作用的机制。这些信息将有助于制定改进的成核和生长模型，并促进在广泛的社会重要应用中更广泛地采用电沉积结构。这种类型的测量在TEM中是可能的，因为BDD具有固有的稳定性，具有极高的热导率，是电子束透明的，不受污染，并且对于多个沉积和成像循环足够鲁棒。此外，该平台可以在这样的条件下运行，即我们有信心我们成像的动态原子事件真正是由于电化学驱动的沉积，而不是其他因素，如电子束诱导的运动。
In electrodeposition the key challenge is to obtain better control over nanostructure morphology. Currently, a lack of understanding exists concerning the initial stages of nucleation and growth, which ultimately impact the physicochemical properties of the resulting entities. Using identical location scanning transmission electron microscopy (STEM), with boron-doped diamond (BDD) serving as both an electron-transparent TEM substrate and electrode, we follow this process, from the formation of an individual metal atom through to a crystalline metal nanoparticle, under potential pulsed conditions. In doing so, we reveal the importance of electrochemically driven atom transport, atom cluster formation, cluster progression to a nanoparticle, and the mechanism by which neighboring particles interact during growth. Such information will help formulate improved nucleation and growth models and promote wider uptake of electrodeposited structures in a wide range of societally important applications. This type of measurement is possible in the TEM because the BDD possesses inherent stability, has an extremely high thermal conductivity, is electron beam transparent, is free from contamination, and is robust enough for multiple deposition and imaging cycles. Moreover, the platform can be operated under conditions such that we have confidence that the dynamic atom events we image are truly due to electrochemically driven deposition and no other factors, such as electron-beam-induced movement.