Zhang Tao, Li Xuejiao, Sun Yiqiang, Liu Dilong, Li Cuncheng, Cai Weiping, Li Yue
Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences Hefei 230031 China
University of Science and Technology of China Hefei 230026 P. R. China.
Chem Sci. 2021 Aug 24;12(38):12631-12639. doi: 10.1039/d1sc03040j. eCollection 2021 Oct 6.
Some of the major difficulties hindering the synthesis of different types of colloidal nanocrystals are their complex synthetic methods and the lack of a universal growth mechanism in one system. Herein, we propose a general strategy of kinetically controlled seed-mediated growth to synthesize a family of penta-twinned gold nanocrystals. Specifically, different kinds of penta-twinned nanocrystals (truncated penta-twinned decahedra, truncated bipyramids, bipyramids, truncated bipyramids with tips, star-like penta-twinned nanocrystals, decahedra with concave edges, and decahedra) with tunable sizes and high purity were readily achieved in one system solely by tailoring the deposition kinetics of adatoms on different sites of decahedral seeds. The controllable deposition kinetics can be realized by changing the ratio of reductant/gold precursors (), which dictates whether horizontal or vertical features along the 5-fold axis direction of Au decahedral seeds are produced. Additionally, the selective growth of a second metal (silver) on penta-twinned gold seeds can be reached through minor modification of , which opens a new avenue for mechanistic investigation by visualizing the seed localization within the final particles. The present work demonstrates a general paradigm for the kinetic growth of penta-twinned crystals and would be extended to the synthesis of other families of nanocrystals.
阻碍不同类型胶体纳米晶体合成的一些主要困难在于其复杂的合成方法以及在一个体系中缺乏通用的生长机制。在此，我们提出一种动力学控制的种子介导生长的通用策略，以合成一族五重孪晶金纳米晶体。具体而言，仅通过调整原子在十面体种子不同位点上的沉积动力学，就能在一个体系中轻松获得具有可调尺寸和高纯度的不同种类的五重孪晶纳米晶体（截顶五重孪晶十面体、截顶双锥体、双锥体、带尖端的截顶双锥体、星状五重孪晶纳米晶体、边缘凹陷的十面体以及十面体）。通过改变还原剂/金前驱体的比例（）可以实现可控的沉积动力学，这决定了沿金十面体种子五重轴方向产生的是水平特征还是垂直特征。此外，通过对进行微小调整，可以实现第二种金属（银）在五重孪晶金种子上的选择性生长，这为通过可视化最终颗粒内的种子定位进行机理研究开辟了一条新途径。目前的工作展示了五重孪晶晶体动力学生长的一般范式，并且将扩展到其他纳米晶体家族的合成。
