论文标题
卤化物作为形状指导剂在纳米颗粒生长中的疗效的计算评估
A Computational Assessment of the Efficacy of Halides as Shape-Directing Agents in Nanoparticle Growth
论文作者
论文摘要
我们报告了一项对黄金和钯纳米颗粒的卤化物吸附的全面研究,该研究解决了一些限制,以阻碍使用原子建模作为理解和改善湿化学合成和相关应用的工具。热力学建模与密度功能理论(DFT)计算和实验数据的组合用于预测卤化物覆盖的纳米颗粒的平衡形状,作为化学环境的函数。为了确保现实和实验相关的结果,我们说明了溶剂的效果,并包括大量的囊泡表面,几个吸附物覆盖范围以及脱头的颗粒。虽然观察到的稳定性不足以导致各向异性形状(如纳米底)的热力学稳定性,但卤化物覆盖范围的不均匀性表明有可能获得动力学等形状。关于技术挑战,我们表明,包含表面溶剂相互作用会导致预测形状的质量变化。此外,在功能水平上考虑非本地相互作用的情况会产生更准确的表面系统描述。
We report a comprehensive study of aqueous halide adsorption on nanoparticles of gold and palladium that addresses several limitations hampering the use of atomistic modeling as a tool for understanding and improving wet-chemical synthesis and related applications. A combination of thermodynamic modeling with density functional theory (DFT) calculations and experimental data is used to predict equilibrium shapes of halide-covered nanoparticles as a function of the chemical environment. To ensure realistic and experimentally relevant results, we account for solvent effects and include a large set of vicinal surfaces, several adsorbate coverages as well as decahedral particles. While the observed stabilization is not significant enough to result in thermodynamic stability of anisotropic shapes such as nanocubes, non-uniformity in the halide coverage indicates the possibility of obtaining such shapes as kinetic products. With regard to technical challenges, we show that inclusion of surface-solvent interactions lead to qualitative changes in the predicted shape. Furthermore, accounting for non-local interactions on the functional level yields a more accurate description of surface systems.