Dendrimers help metals come together at small scales

Researchers in Japan have found a way to create innovative materials by blending metals with precision. Their approach, based on a concept called atom hybridization and reported in a paper in Nature Communications, opens up an unexplored area of chemistry that could lead to the development of advanced functional materials.

Multimetallic clusters – typically composed of three or more metals – are garnering attention as they exhibit properties that cannot be attained by single-metal materials. Blending various metal elements together offers the promise of producing as-yet-unknown substances and highly-functional materials.

So far, though, no one had reported multimetallic clusters blended with more than four metal elements, because of the tendency of the different metals to separate. One idea for overcoming this problem is to miniaturize cluster sizes to a scale of 1nm, thereby forcing the different metals to blend together in a small space. But there has been no way to realize this idea.

A Japanese team, including Takamasa Tsukamoto, Takane Imaoka, Kimihisa Yamamoto and colleagues from the Tokyo Institute of Technology, has now developed an atom hybridization method for achieving the first-ever synthesis of multimetallic clusters consisting of more than five metal elements, with precise control over size and composition. Their method employs a dendrimer template that serves as a tiny ‘scaffold’ to allow the controlled accumulation of metal salts. After precise uptake of the different metals into the dendrimer, multimetallic clusters are then obtained by chemical reduction. In contrast, a conventional method without the dendrimer produces larger clusters and results in the separation of the different metals.

The team successfully demonstrated the formation of five-element clusters composed of various combinations of gallium (Ga), indium (In), gold (Au), bismuth (Bi) and tin (Sn), as well as iron (Fe), palladium (Pd), rhodium (Rh), antimony (Sb) and copper (Cu). It also demonstrated a six-element cluster consisting of Ga, In, Au, Bi, Sn and platinum (Pt). Additionally, the researchers hint at the possibility of making clusters composed of eight metals or more.

There are more than 90 metals in the periodic table. With infinite combinations of metal elements, atomicity and composition, this atom hybridization method will open up a new field in chemistry on a 1nm scale. The current study marks a major step forward in creating as-yet-unknown innovative materials.

This story is adapted from material from the Tokyo Institute of Technology, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.