A novel method for creating tiny, three-dimensional materials has been demonstrated by scientists from UNSW Sydney. This method has the potential to eventually make fuel cells like hydrogen batteries cheaper and more sustainable.
Researchers from UNSW Science's School of Chemistry demonstrate in a study that has been published in Science Advances that it is possible to sequentially "grow" interconnected hierarchical structures at the nanoscale in three dimensions with unique chemical and physical properties to support energy conversion reactions.
Hierarchical structures in chemistry are arrangements of units, such as molecules, within an organization of other units that can be ordered. Similar phenomena can be observed in things like flower petals and tree branches in the natural world. However, these structures have extraordinary potential at a nanoscale that is invisible to the naked eye.
Assembling Hierarchical-Type Structures
Researchers have found it challenging to replicate these three-dimensional structures with nanoscale metal components using conventional approaches. Ten millimeters are contained in a centimeter to comprehend how tiny these tiny 3D materials must be. Each of those millimeters would be one nanometre, or nm, if one million tiny segments were counted in just one. Professor Richard Tilley, the senior author of the study and the Director of the Electron Microscope Unit at UNSW, states that up to date, scientists were able to assemble hierarchical-type structures on the micrometer or molecular scale, as reported by Phys.
Furthermore, they needed to construct a brand-new bottom-up tool to get the level of precision needed for the nanoscale assembly. Due to the direct connection of a metallic core and branches, the resulting interconnected 3D nanostructure has a high surface area, high conductivity, and chemically alterable surfaces. The ideal electrocatalyst support- is a substance that speeds up reactions in the oxygen evolution reaction, an essential energy conversion process because of these properties. The Electron Microscope Unit provided cutting-edge electron microscopes, and electrochemical analysis was used to investigate the properties of the nanostructure.
The study's lead author, Dr. Lucy Gloag, a Postdoctoral Fellow at UNSW Science, mentioned that growing the nanomaterial step by step contrasts with what the team does to compose the structures at the micrometer level, which is starting with bulk material and etching it down. The scientists can keep all of the elements ultra-small on the nanoscale, where the distinct catalytic properties exist, thanks to the new method that gives the team excellent control over the conditions.
Hydrogen Into Electricity
Most of the atoms in conventional catalysts, typically spherical, are stuck in the middle of the sphere. Since there are very few atoms on the surface, most of the material is wasted because it cannot participate in the environment of the reaction. According to Prof. Tilley, these new 3D nanostructures are designed to expose more atoms to the reaction environment, allowing for more effective and efficient energy conversion catalysis.
Prof. Tilley asserts that having a higher surface area for the catalyst can cause the reaction to be more efficient when converting the hydrogen into electricity if utilized in a fuel cell or battery. Additionally, Dr. Gloag indicates that the reaction requires less material. It will eventually lessen costs, make energy production more renewable, and shift human dependence away from fossil fuels.
The next research stage will focus on using platinum, a more expensive but superior catalytic metal, on altering the material's surface. The platinum that powers the fuel cell makes up about a sixth of the total cost of an electric vehicle. Prof. Tilley mentioned that the exceptionally high surface areas could support an element like platinum to be layered on in individual atoms. As a result, they have the absolute best use of these expensive metals in a reaction environment.
RELATED ARTICLE : Nanoscale Materials Derived From Rare Experiments Poses Medicine and Energy Potential
Check out more news and information on Nanotechnology in Science Times.
