In the heart of Japan, researchers at Osaka University have made a significant stride in understanding the atomic-scale chemistry of cerium dioxide, a material with immense potential in the energy sector. Kyungmin Kim, a researcher at the Graduate School of Engineering Science, led a team that employed advanced scanning techniques to unravel the mysteries of partially reduced cerium dioxide surfaces.
Cerium dioxide, or ceria, is a metal oxide that has garnered considerable attention due to its exceptional redox properties. These properties are closely tied to the formation of oxygen vacancies and the associated charging of cerium atoms. “Understanding these processes at the atomic scale is crucial for developing more efficient catalysts and other energy-related materials,” Kim explained.
The team utilized a combination of scanning tunneling microscopy (STM) and atomic force microscopy (AFM), along with force spectroscopy, to characterize the surface of partially reduced ceria samples. STM images revealed electronic modulations of the atomic contrast, while AFM provided clear differentiation of these electronic features from the true topographic atomic structure. Force spectroscopy, using carbon monoxide functionalized probes, quantified the chemical reactivity of the cerium atoms.
“This study demonstrates that the combination of STM with AFM and force spectroscopy bears great potential to provide robust atomic-level insights into the chemistry of defects at ceria surfaces,” Kim said. The research was published in the journal ‘Science and Technology of Advanced Materials’, which translates to ‘Materials Research Bulletin’ in English.
The implications of this research are far-reaching, particularly for the energy sector. Ceria-based catalysts are used in various applications, including fuel cells, solar cells, and environmental catalysis. By gaining a deeper understanding of the atomic-scale chemistry of ceria, researchers can develop more efficient and cost-effective catalysts, ultimately contributing to the advancement of clean energy technologies.
Moreover, the techniques employed in this study could be applied to other materials, paving the way for further advancements in materials science. As Kim noted, “This approach could be extended to other oxide surfaces, providing valuable insights into their chemistry and potential applications.”
In the quest for cleaner and more sustainable energy solutions, every atomic-scale discovery brings us one step closer to a brighter future. The work of Kim and his team at Osaka University is a testament to the power of advanced microscopy techniques in unraveling the complexities of materials science, with significant implications for the energy sector.