Hydrogen peroxide (H 2 O 2 ) is an environmentally friendly and versatile chemical widely used in paper bleaching, water treatment, and as a green oxidant for organic synthesis. Global demand for H 2 O 2 has risen significantly in recent years, driven largely by its role as a disinfectant and oxidizing agent. However, the current industrial production method—the energy-intensive anthraquinone process—requires high operating pressures (>2.0 MPa), generates organic waste, and poses safety and environmental concerns. Moreover, transporting and storing concentrated H 2 O 2 solutions incur high costs. A more sustainable and mild synthesis route is urgently needed.
A research team led by Prof. Jun Bao from the National Synchrotron Radiation Laboratory at the University of Science and Technology of China has now developed a synergistic PtPd-Al 2 O 3 catalytic system that enables highly selective and stable electrochemical production of H 2 O 2 via the two-electron oxygen reduction reaction (2e⁻ ORR) under neutral conditions. The team published their findings in Nano Research on July 3, 2026.
The electrochemical 2e⁻ ORR pathway has emerged as a promising method for H 2 O 2 generation due to its eco-friendliness and sustainable operation. However, the primary challenges lie in developing catalysts with high selectivity and long-term stability, particularly under neutral conditions. Neutral electrosynthesis is especially attractive for applications such as disinfection and environmental decontamination. Yet the low hydroxyl ion concentration in neutral electrolytes hinders effective binding of *OOH: the key intermediate in the 2e⁻ ORR process.
The PtPd-Al₂O₃ catalyst was synthesized through a co-reduction reaction of platinum and palladium precursors on a γ-Al 2 O 3 substrate. Synchrotron radiation CO-DRIFTS measurements showed that as palladium content increased, the CO-DRIFTS peak progressively red-shifted––a characteristic correlated with an upshift in the d-band center. Transmission electron microscopy revealed ultrafine nanoparticles uniformly dispersed on the alumina nanosheet support, with an average size of 2.89 nm. High-angle annular dark-field scanning transmission electron microscopy confirmed that palladium atoms were uniformly incorporated into the PtPd lattice, altering the surface geometry of the nanoparticles.
The electrocatalytic performance was evaluated using a rotating ring-disk electrode in 0.1 M Na 2 SO 4 . PtPd-Al 2 O 3 displayed outstanding 2e⁻ ORR activity with a selectivity of 92-96% across a wide potential range from 0 to 0.6 V, compared to just 15% for Pt-Al 2 O 3 and 10% for Pd-Al 2 O 3 . The electron transfer number for PtPd-Al 2 O 3 was 2.08, confirming the dominant 2e⁻ pathway, whereas the Pt and Pd catalysts followed the typical 4e⁻ pathway with transfer numbers of 3.79 and 3.85, respectively. In a three-chamber flow cell reactor, PtPd-Al₂O₃ achieved significantly higher normalized H₂O₂ current densities, consistently exhibiting over 80% Faradic efficiency at a current density of -200 mA cm -2 . Remarkably, the catalyst maintained high Faradic efficiency exceeding 80% at -50 mA cm -2 for over 20 hours, demonstrating outstanding durability.
To understand the origin of this remarkable performance, the team conducted in-situ X-ray absorption fine structure measurements during the ORR process. While platinum in Pt-Al 2 O 3 underwent dynamic oxidation and structural reconstruction under applied potential, the coordination environment of platinum in PtPd-Al 2 O 3 remained remarkably stable. The Pt–Pt and Pt–Pd bond lengths stayed largely constant, and the palladium coordination number increased from 2.12 to 3.41 under applied potential—indicating a potential-induced reconstructing behavior that protected the catalyst from excessive oxidation. “The incorporation of palladium atoms enhanced the structural stability of the nanoparticles, thereby improving the electrocatalytic durability for the 2e⁻ ORR under neutral conditions” the team noted. In-situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy further revealed that characteristic peaks for *O 2 and *OOH intermediates accumulated on the PtPd-Al 2 O 3 surface under operating potentials, confirming the catalyst’s superior capability to stabilize these key intermediates. DFT calculations confirmed electron transfer from Pd to Pt, upshifting the d-band center of PtPd, consistent with CO-DRIFTS. Bader charge analysis revealed Pt and Pd sites with distinct electronic characters. Pt sites favored end-on *OOH adsorption leading to H 2 O 2 , while Pd’s strong oxophilicity induced O–O bond cleavage.
“This work not only provided a high-performance catalyst for H 2 O 2 electrosynthesis but also demonstrated a general strategy to stabilize noble metal catalysts via d-band manipulation and coordination environment engineering, which could be extended to other electrochemical transformations such as CO 2 reduction and alcohol oxidation,” the research team concluded.
“We thank the staff members of BL01B and BL20U beamline at SSRF in Shanghai, the BL12B-a beamline at NSRL in Hefei, for providing technical support in data collection. Also, we thank the USTC supercomputing center for providing computational resources for this project.” the research team concluded. The research was led by Prof. Jun Bao at the National Synchrotron Radiation Laboratory, Anhui Industrial Innovation Research Institute of Advanced Optoelectronic Materials and Systems, University of Science and Technology of China. This work was supported by National Natural Science Foundation of China (12241502, 22509196); the open research fund of Key Laboratory of Precision and Intelligent Chemistry; Fellowship of China Postdoctoral Science Foundation (2025T180276); Anhui Provincial Natural Science Foundation (2508085QB044).
DOI Link:
https://doi.org/10.26599/NR.2026.94908995
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 8,000 articles. In 2025 InCites Journal Citation Reports, its 2025 IF is 9.4 (8.3, 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.
Nano Research
Synergistic effects in Pt-Pd binary electrocatalyst for efficient hydrogen peroxide electrosynthesis
3-Jul-2026