Identical properties, low cost – Copper-based alternative for next-generation electronics

Japanese scientists have developed a technique that turns a copper-based substance into a material that replicates precious and expensive metal properties, such as gold and silver. The new support, consisting of copper nanoparticles (very small copper-based structures), has promising applications in the production of electronic devices that would otherwise depend on their expensive counterparts in gold and silver. It is also suitable for the manufacture of electronic components using printing technologies recognized as environmentally friendly production methods. The study was published on January 29 in Scientific reports.

The development of the Internet of Things (IoT) has rapidly increased the demand for thin and portable electronic devices. For example, IoT depends on communication between devices, which requires antennas that have until now required gold-based metal composites and costly silver.

To date, existing techniques for the preparation of copper nanoparticles were not ideal because they resulted in the attachment of impurities to the material. Since these impurities could only be removed by extremely high temperatures, the copper nanoparticles created at room temperature were impure and therefore could not solidify into usable parts. Until now, this has been one of the obstacles to creating a more profitable alternative to gold and silver coins in electronic devices.

The joint study conducted by researchers from the University of Tohoku and Mitsui Mining & Smelting Co., Ltd. in Tokyo revealed the successful synthesis of copper nanoparticles able to solidify at much lower temperatures while by remaining pure. The team modified the structure of the copper nanoparticles and made them more stable so that they do not degrade at low temperatures.

"Copper is an attractive alternative material in the preparation of electrical circuits.The most important part of using copper is to modify it so that it solidifies at low temperatures." now, it was difficult because copper interacts easily with air humidity. With the methods used in this study that modify the carbon structure and thus make it more stable, we managed to overcome this instability problem, "adds Kiyoshi Kanie, Ph.D., associate professor at the Institute of Multidisciplinary Research on Advanced Materials of Tohoku University.

The researchers hope to develop the application of their copper-based nanoparticles beyond the electronics. They think that this material will also be useful in other areas. "Our method has effectively created materials based on copper nanoparticles that can be used in various types of portable and flexible on-demand devices that can be easily manufactured at a very low cost through printing processes," adds Kanie.