Atomic-level local-structure engineering of Pt-group oxygen electrocatalysts for fuel cells and water electrolyzers
image: Optimizing the local structure of Pt-group oxygen electrocatalysts at the atomic level for fuel cells and electrolyzers was hilighted, including the general synthesis methods, typical characterizations, design considerations, and electrocatalysis applications.
Credit: Nano Research Tsinghua University Press
Proton exchange membrane fuel cells (PEMFCs) and proton exchange membrane water electrolyzers (PEMWEs) are key devices for achieving efficient "hydrogen-electricity" conversion. They have attracted significant attention due to their high energy conversion efficiency and zero carbon emissions. However, their core component, oxygen reduction/evolution (ORR/OER) electrocatalysts, still face challenges of activity and stability. Among them, platinum-group catalysts (such as Pt, Ir, Ru) are currently the most effective ORR/OER catalysts, but issues like their scarcity and high cost severely limit their large-scale utilization in PEMFCs/PEMWEs. Single-atom catalysts (SACs) and multi-atom catalysts (MACs), with their nearly 100% metal utilization rate and unique electronic structures, provide a new path for developing low-loading, high-activity, and high-stability platinum-group catalysts.
Team of energy material scientists led by Xinbo Zhang from Changchun Institute of Applied Chemistry, Chinese Academy of Sciences in Changchun and Kebin Chi from Petrochemical Research Institute, PetroChina in Beijing, China recently outlined progress of Pt-group single- or multiple-atom catalysts (SACs/MACs) for ORR and OER. Universal synthesis methods to prepare Pt-group single- or multiple-atom catalysts (SACs/MACs) are discussed, with a focus on crucial factors that affect the structure and catalytic performance. And advanced characterization techniques for directly confirming atomically dispersed metal atoms were also introduced. Important considerations for rational catalyst design and progress of Pt-group SACs/MACs are then summarized regarding tailoring atomically dispersed metal sites and various supports, and contribution of metal-support interaction on the catalytic performance. Key challenges and perspectives for future development are briefly discussed.
The team published their review in Nano Research on December 30, 2025.
The review outlines several advanced synthesis techniques, including wet chemistry methods (e.g., impregnation, coprecipitation, confinement, and electrodeposition), atomic layer deposition (ALD), high-temperature pyrolysis, and high-energy ball milling. In spite their advatangeds, limitation of these current methods is also hilighted in a precise control over the distribution and coordination of metal atoms on various supports, maximizing metal utilization and catalytic efficiency toward pratical aplication.
The research team further summarized advanced characterization techniques. In particular, techniques such as aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (AC-HAADF-STEM) and X-ray absorption spectroscopy (XAFS) allow researchers to directly observe and verify the atomic dispersion and local environment of metal sites. In-situ and operando methods provide real-time insights into the underlying process of generating catalytic phase and the catalyst behavior under reaction conditions. These advanced characterization techniques provide key information for the design of platinum group oxygen electrocatalysts, significantly advancing the development process of high-performance oxygen electrocatalysts.
The research team pointed out that the local coordination environment around the atom and the kinds of supports play a crucial role in regulating the activity and stability of catalysts. The electronic and geometric structure of metal centers—such as Pt–N, Ir–O, or Ru–N motifs—can be tailored to optimize intermediate adsorption and reaction pathways. Strong metal-support interactions and the use of conductive, corrosion-resistant supports (e.g., doped carbons, metal oxides, and MOFs) are critical for enhancing both activity and stability.
This review underscores the transformative potential of atomically dispersed Pt-group catalysts in making hydrogen energy technologies more efficient, durable, and cost-effective. Despite progress, challenges remain—including the scalable synthesis of high-loading SACs, prevention of metal aggregation, and the need for deeper mechanistic understanding through advanced in-situ characterization.
Other contributors include Yang Ji, Haixia Zhong, Cani Ma, Qinyi Hu, and Xinbo Zhang from Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, in Changchun and the University of Science and Technology of China in Hefei, China; Liang Qiao and Kebin Chi from Petrochemical Research Institute, PetroChina in Beijing, China; and Yuri Nikolaichik from Belarusian National Technical University in Minsk, Belarus.
This work was supported by the National Key R&D Program of China (2021YFB4000603), the National Natural Science Foundation of China (52273277 and U24A2062), Jilin Province Science and Technology Development Plan Funding Project (SKL202302039), and Youth Innovation Promotion Association CAS (2021223). H.X.Z. acknowledges funding from the National Natural Science Foundation of China Outstanding Youth Science Foundation of China (Overseas).
About Nano Research
Nano Research is a peer-reviewed, open access, international and interdisciplinary research journal, sponsored by Tsinghua University and the Chinese Chemical Society, published by Tsinghua University Press on the platform SciOpen. It publishes original high-quality research and significant review articles on all aspects of nanoscience and nanotechnology, ranging from basic aspects of the science of nanoscale materials to practical applications of such materials. After 18 years of development, it has become one of the most influential academic journals in the nano field. Nano Research has published more than 1,000 papers every year from 2022, with its cumulative count surpassing 7,000 articles. In 2024 InCites Journal Citation Reports, its 2024 IF is 9.0 (8.7, 5 years), and it continues to be the Q1 area among the four subject classifications. Nano Research Award, established by Nano Research together with TUP and Springer Nature in 2013, and Nano Research Young Innovators (NR45) Awards, established by Nano Research in 2018, have become international academic awards with global influence.