Gold quantum needles could sharpen imaging resolution and boost energy conversion

The researchers Shinjiro Takano, Yuya Hamasaki and Tatsuya Tsukuda of the University of Tokyo managed to visualize the geometric structure of the growing golden nanoclusters in their early stages. During this process, they also successfully developed a new structure of elongated nanoclusters, which they named quantum gold needles.

Thanks to their light reactivity in the nearby infrared range, these needles could allow much higher resolution biomedical imaging and more efficient light energy conversion. The results were published in the Journal of the American Chemical Society.

Although gold can evoke pump and luxury images, it is also an essential element of modern nanotechnology because of its unique structures and properties on a nanometric scale.

Golden nanoclusters composed of less than 100 atoms are generally synthesized by reduction, that is to say electrons, golden pioneers in the presence of protective ligands. However, the synthesis of golden nanoclusters of the desired size, shape and composition is always a challenge.

“In recent years,” said Tsukuda, principal researcher, “many efforts have been devoted to understanding the correlation between the structure and the physicochemical properties of nanoclusters. However, the training process is considered a black box.

The researchers decided to determine the geometric structures of golden nanoclusters at the initial stages of their training. They used slightly unusual summary conditions to trap nanoclusters in the very early stages of growth.

The diffraction analysis of the monocrystallic X -rays, an x ​​-ray for chemical compounds, if you want, revealed that golden nanoclusters have developed in anisotropically, at a different pace in different directions. In addition, the analysis revealed an entirely new structure: nanoclusters in the form of pencil composed of triangular and tetrahedral tetramers.

The researchers named them quantum gold needles because the electrons confined to these nanoclusters have demonstrated a quantified behavior, a quantum phenomenon in which electrons can only take specific potential energies.

“We could retroactively explain the training processes of a series of small golden nanoclusters in our unusual synthetic conditions,” explains Tsukuda.

“However, the formation of needles with a base of a triangle of three gold atoms instead of an almost spherical cluster is a fortuitous discovery which was far beyond our imagination.”

The structural snapshots that researchers have acquired from the step -by -step growth of golden nanoclusters contribute considerably to our understanding of the training mechanism. However, Tsukuda is already thinking of the next steps.

“We would like to explore the synthesis of other unique nanoclusters by further refining the summary conditions. We would also like to collaborate with other experts to promote the application of quantum gold needles, by taking advantage of their exceptional optical properties.”