Green energy is a quickly evolving industry that is always looking for ways to improve, and recent developments in dual-atom catalysts have the potential to completely transform energy conversion technology.
Image Credit: Natali Mis/Shutterstock.com
Rapid, effective, and scalable technologies are essential for the search of sustainable substitutes for carbon-based energy sources. A viable option is water-splitting systems (WWSs), which run on solar-powered batteries. However, WWSs scalability for widespread usage is limited by the complex and sluggish reaction phases that are inherent to it.
Researchers from Qingdao Institute of Bioenergy and Bioprocess Technology of the Chinese Academy of Sciences looked for a better design to boost the stability and speed of the three main half reactions—oxygen evolution, hydrogen evolution, and reduction reactions—that are necessary for WSSs to operate at a high level.
It turns out that there is additional potential to enhance the kinetics and multifunctional performance of oxygen reduction/evolution and hydrogen evolution reactions with dual-atom catalysts, which bridge the gap between single-atom and metal/alloy nanoparticle catalysts. On November 8th, 2023, their findings were published in Nature Communications.
Oxygen reduction/evolution and hydrogen evolution reactions are the core reactions, involving multi-proton-electron coupling processes, which are kinetically slow, so it is urgent to develop efficient, stable, and low-cost electrocatalytic materials to improve their conversion efficiency.
Heqing Jiang, Study Corresponding Author, Chinese Academy of Sciences
Dual-atom catalysts (DACs) are important in the field of energy catalysis because of their advantageous multifunctional catalytic activity, higher atomic utilization efficiency, and more effective disruption of the linear relationship with reaction intermediates. In contrast, single-atom catalysts (SACs) only have one metal atom per active site.
Furthermore, because SACs have larger reaction barriers, using them in energy conversion systems will severely reduce energy conversion efficiency. Because of the complementary effects between their two metal atoms, DACs may effectively modulate the cooperative effects between their two active sites, leading to a significant decrease in the energy barriers needed for the reaction.
Given the benefits of DACs, it is imperative to investigate their synthesis mechanism using high-temperature sintering techniques to progress their preparation and enable commercial applications.
We reported a novel atomization/sintering strategy to synthesize and tune the configuration states of cobalt (Co) species at the atomic level, from nanoparticles to single-atom to dual-atom.
Minghua Huang, Study Author, Chinese Academy of Sciences
In the atomization/sintering technique, cobalt is first converted into nanoparticles (atomization), which are subsequently employed in the sintering process to generate single atom (SA) and dual atom (DA) species. A noteworthy aspect of this approach and the research findings is the potential applications of atomization/sintering to produce 21 more DACs.
All of this is the result of studying the atomization/sintering process used to generate these DACs. The more DACs there are, the more chances there are to look into other ways to harness energy sustainably more effectively.
Promising outcomes were observed when the dual-atom Co2 N5 was tested in zinc-air batteries. The Zn-air batteries demonstrated the capability for continuous operation even at night, with a stability of 800 hours and the ability to split water continuously for 1,000 hours at a time.
Heqing Jiang added, “This universal and scalable strategy provides opportunities for the controlled design of efficient multifunctional dual atom catalysts in energy conversion technologies.”
Bimetallic catalysts can continue to be improved by making more advancements. It can also be educational to observe how they function in various situations, such as how the water-splitting mechanism handles seawater or frigid temperatures. Putting these devices in challenging environments can draw attention to issues that still need to be resolved and may prevent widespread or commercial deployment.
Journal Reference:
Wang, X., et al. (2023) Developing a class of dual atom materials for multifunctional catalytic reactions. Nature Communication doi.org/10.1038/s41467-023-42756-8
Source: https://english.cas.cn/