Laser ablation enables scalable production of nanotwinned PtCo electrocatalysts with enhanced stability for proton-exchange membrane fuel cells

High stacking-fault-energy metals are difficult to engineer with stable twin boundaries, limiting their practical use. Laser ablation offers an efficient way to create nanotwinning in PtCo electrocatalysts, enabling new possibilities for such metals.

A research group led by Yu Huang at the University of California, Los Angeles (UCLA) has recently published a novel synthetic strategy for introducing nanotwinning in platinum-based electrocatalysts through laser ablation. The PtCo electrocatalyst produced using this technique achieves a nanotwinning yield of over 60%, a substantial improvement compared to the 12% yield observed in commercial benchmarks. The nanotwinned architecture enhances stability in proton-exchange membrane fuel cell (PEMFC) evaluations, resulting in a mass activity (MA) of 0.56 A mgPt⁻¹ and achieving 82.1% retention following accelerated stress testing—both metrics exceeding the U.S. Department of Energy (DOE) 2025 targets. Additionally, the process is characterized by rapid throughput and low energy requirements, positioning laser ablation as a promising approach for scalable catalyst production and high-throughput screening.

This study was published in Nano Research on November 13, 2025.

Twinning, defined by mirror-like interfaces within crystals, is well regarded for its contributions to mechanical strength, thermal stability, and catalytic efficiency. Nonetheless, achieving controlled synthesis is complex, necessitating a careful equilibrium between thermodynamic stability and kinetic trapping during twin formation. Traditional approaches, such as mechanical deformation or thermal processing, can generate nanotwinning in metals with low stacking-fault energies—such as copper or gold—yet effective methodologies for producing nanotwinned structures in metals like platinum remain under investigation.

Researchers at UCLA utilized laser ablation, which employs high-energy laser pulses and rapid cooling rates reaching up to 10^8 K s^-1, allowing for precise manipulation of nanostructure via swift melting and solidification, thereby promoting the development of metastable formations such as nanotwins. By systematically adjusting critical laser variables—namely power and exposure duration—the team attained an outstanding nanotwinning yield of 61% in PtCo nanoparticles. Proton Exchange Membrane Fuel Cell (PEMFC) evaluations of the nanotwinned PtCo catalyst demonstrated superior results, with mass activity surpassing U.S. DOE benchmarks and voltage loss remaining below DOE requirements. Subsequent structural analysis indicated that the nanotwinned catalysts effectively restrained particle enlargement and cobalt loss, maintaining alloy integrity and morphology significantly better than commercial alternatives.

To examine the mechanisms underlying nanotwinning formation, the research team conducted controlled experiments involving laser ablation on commercial Pt and PtCo catalysts. They identified two primary mechanisms: (1) particle migration and agglomeration resulting from exposure to high-energy laser irradiation, followed by rapid cooling that stabilizes intermediate metastable structures and facilitates nanotwin development; and (2) the presence of Co, which markedly reduces the stacking-fault energy of Pt, promotes atomic diffusion even under lower-energy stimuli, and consequently increases the propensity for nanotwinning.

Furthermore, a techno-economic analysis demonstrated that the laser ablation process offers several advantages over traditional wet-chemical synthesis methods, such as reduced energy consumption and expedited processing times. This technique can also be applied to other alloy systems, presenting new opportunities for high-throughput exploration of metastable materials and scalable catalyst manufacturing.

Yu Huang the corresponding author of the article, professor in both the Department of Materials Science and Engineering and the Department of Chemistry and Biochemistry at UCLA. Dr. Huang is also the Traugott and Dorothea Frederking Endowed Chair in Engineering at UCLA.

Co–first authors of the article are Jin Huang and Yu-Han Joseph Tsai from UCLA. Other contributors include Shiqi Zheng, Ao Zhang, Sibo Wang, Heting Pu, Bosi Peng, Zeyan Liu, Ting-Jung Hsiao, Prof. Xiangfeng Duan, and Prof. Y. Morris Wang from UCLA; as well as Prof. Bingbing Li from the Terasaki Institute for Biomedical Innovation and the Department of Manufacturing Systems Engineering and Management at California State University, Northridge.

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.