Departamento de Química Física and Unidad Asociada CSIC - Universidade de Vigo, 36310, Vigo, Spain.
Nanoscale. 2010 Nov;2(11):2377-83. doi: 10.1039/c0nr00239a. Epub 2010 Aug 12.
The growth mechanism from pentatwinned (PTW) gold nanorods into truncated quasi-decahedral particles when a gold salt (HAuCl₄) is reduced by N, N-dimethylformamide (DMF) in the presence of poly(vinylpyrrolidone), was elucidated through a combination of different techniques, including transmission and scanning electron microscopy, high resolution TEM and selected area electron diffraction. Particles with intermediate shapes between the original pentatwinned Au nanorods, used as seeds, and the final quasi-decahedral particles were obtained by simply tuning the [HAuCl₄] to [seeds] ratio. From the thorough structural analysis of all the intermediate morphologies obtained, it was concluded that gradual morphology changes are related to the preferential growth of higher energy crystallographic facets. As a result of the particle growth and concomitant decreased anisotropy, a progressive blue-shift of the surface plasmon resonance bands of the nanoparticles was registered by vis-NIR extinction spectroscopy.
通过透射电子显微镜和扫描电子显微镜、高分辨率透射电子显微镜和选区电子衍射的组合，阐明了在聚（N-乙烯基吡咯烷酮）存在下，由五重孪晶（PTW）金纳米棒在金盐（HAuCl₄）被 N，N-二甲基甲酰胺（DMF）还原时生长成截角十面体颗粒的生长机制。通过简单地调节[HAuCl₄]与[种子]的比例，获得了原始五重孪晶 Au 纳米棒作为种子和最终准十面体颗粒之间的中间形状的颗粒。通过对所有获得的中间形态的彻底结构分析，得出结论，逐渐的形态变化与优先生长的高能量晶面有关。由于颗粒的生长和随之而来的各向异性的降低，通过可见近红外消光谱法记录了纳米颗粒表面等离子体共振带的逐渐蓝移。
