The quest for sustainable energy solutions has placed green hydrogen at the forefront, but its economic viability relies on overcoming the high cost of the catalysts that produce it. The oxygen evolution reaction (OER), a critical but sluggish process in water electrolysis, has long depended on expensive and rare iridium. Now, a research team has developed a high-performance catalyst using more abundant materials, offering a promising path to cheaper green hydrogen.
Scientists from Shaoxing University, in collaboration with Taizhou University, ERA Co., Ltd. and Tsinghua University, have engineered a novel electrocatalyst, SrPd₃₋ₓRuₓO₄/SrRuO₃, using an innovative "heterojunction-doping synergy" strategy. This material exhibits superior OER activity and remarkable stability, positioning it as a viable and cost-effective alternative to iridium-based catalysts. The study was recently published in a leading scientific journal.
"The most important message from our work is that we have successfully moved beyond simply mimicking existing catalysts," said Professor Wenwu Zhong, a co-corresponding author of the study from Shaoxing University. "By rationally combining heterojunction construction and atomic doping, we created a synergistic effect that dramatically enhances both activity and durability. This is a new design paradigm, not just a new material."
The team's approach involved partially substituting palladium (Pd) atoms with ruthenium (Ru) in a SrPd3O4 matrix. This process not only tunes the electronic structure but also triggers the spontaneous formation of a heterojunction with SrRuO3. The resulting interface facilitates ultra-efficient charge transfer, while the doped Ru atoms optimize the catalyst's surface for the OER intermediates.
The performance results are striking. In laboratory tests under alkaline conditions (1 M KOH), the optimized catalyst required an overpotential of only 227.6 mV to achieve a current density of 10 mA cm⁻², a standard metric for OER activity. Crucially, it demonstrated exceptional long-term stability, operating continuously for over 300 hours at a high current density of 50 mA cm⁻²without significant degradation.
The research is significant because it addresses the primary cost barrier to scaling up electrolyzer technology. Replacing or reducing the reliance on iridium without compromising performance is a major goal for the hydrogen industry.
"The ultimate goal is to contribute to a sustainable energy future," Prof. Zhong added. "The next step for us is to explore scaling up the synthesis of this catalyst and integrating it into commercial electrolyzer systems. The potential applications are vast, from large-scale hydrogen production plants for industry and energy storage to smaller, distributed electrolyzers for refueling stations."
This work not only provides a specific candidate material but also a generalizable strategy for designing high-performance catalysts for other energy conversion and storage technologies.
The study was conducted by researchers from Zhejiang Key Laboratory for Island Green Energy and New Materials, ERA Co., Ltd., and the Beijing National Center for Electron Microscopy at Tsinghua University.
This work was financially supported by the National Natural Science Foundation of China and the Natural Science Foundation of Zhejiang Province.
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.
