Nanostructured two-dimensional gold monolayers open up exciting opportunities in catalysis, electronics, and nanotechnology.
Researchers have successfully developed nearly freestanding nanostructured two-dimensional (2D) gold monolayers, a remarkable achievement in nanomaterial engineering that may lead to new possibilities in catalysis, electronics, and energy conversion.
Gold is an inert metal that generally forms solid three-dimensional (3D) structures. However, when it is crafted into a 2D form, it exhibits remarkable properties, including distinct electronic behaviors, improved surface reactivity, and vast potential for groundbreaking uses in catalysis and advanced electronics.
One major challenge in producing 2D gold monolayers has been ensuring the stability of isotropic metallic bonds in a purely 2D format. To overcome this issue, a research team from Lund University and Hokkaido University utilized an innovative bottom-up approach alongside high-performance computations, allowing them to create large-scale gold monolayers with distinctive nanostructured patterns, exceptional thermal stability, and promising catalytic properties.
The team fabricated gold monolayers on an iridium substrate and introduced boron atoms at the interface between the gold and iridium. This cutting-edge method resulted in the creation of suspended monoatomic sheets of gold, characterized by a hexagonal structure featuring nanoscale triangular patterns. The incorporation of boron significantly improved the stability and structural robustness of the gold layers, facilitating the formation of the nanostructures.
“The simplicity of preparation and the thermal stability of the resulting gold films are noteworthy, making them a viable platform for additional investigations into the fundamental properties of elemental 2D metals and their potential applications in electronics and nanotechnology,” states Dr. Alexei Preobrajenski from MAX IV Laboratory at Lund University, who is one of the lead authors of the study.
To investigate the structural and electronic properties of the gold films, the researchers employed advanced characterization techniques such as scanning tunneling microscopy (STM) and X-ray spectroscopy. Their analyses indicated that the inclusion of boron aids in the transition from 3D to predominantly 2D metal bonding, significantly changing the electronic characteristics of the gold layers. This shift highlights the distinctive nature of the synthesized films, as conventional methods often fail to produce stable 2D metallic forms, resulting in small or unstable structures instead.
The capacity to generate stable and almost freestanding metallic monolayers over a large area has extensive implications. “This research paves the way for testing theories and further investigating the potential uses of 2D metals across various fields, including catalysis and energy conversion,” notes Associate Professor Andrey Lyalin from the Faculty of Science at Hokkaido University, who is another lead author of the study.
By tackling the difficulties associated with stabilizing 2D metallic materials, this research enhances the understanding of 2D materials and sets the stage for prospective technological applications.
