Abstract
The compositional heterogeneity of post-consumer plastic waste, exemplified by prevalent polyethylene (PE)/polypropylene (PP) mixtures (>50% of the plastic market), severely complicates recycling. Kinetic disparities between PE and PP during chemical recycling create significant conversion gradients, limiting valued product yield and process viability. Here, leveraging strong interfacial coupling between ruthenium oxides and rutile TiO2, we construct highly active, epitaxial RuOx sites enabling efficient one-pot co-conversion of PE/PP mixtures with a high liquid yield of 95.02%, while maintaining a low 0.62% gas yield. Compared to conventional Ru nanoparticles, the epitaxial RuOx structure provides additional dehydrogenation sites for PP activation, which promotes carbon–metal back-donation to weaken C–C bonds, thus exhibiting comparable activation capabilities toward both 3C–2C bond in PP and 2C–2C bond in PE. This unique epitaxial catalyst enables highly efficient co-hydrogenolysis of mixed polyolefins, establishing a practical approach for their upcycling.
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The source data generated in this study are provided in the Source Data file. All data are available from the corresponding author upon request. Source data are provided with this paper.
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Acknowledgments
This work was supported by the National Natural Science Foundation of China (No. 22376152 to J.C. and No. 42377013 to M.X.Z.), Jiangsu Provincial Fund for Excellent Young Scholars (BK20240154 to J.C.), and Suzhou Frontier Technology Research Advanced Materials Project (SYG202305 to J.C.). M.Z. thanks the support from Zhejiang Provincial Key Research and Development Program (2025C02207). J.C. thanks the support from the Suzhou Key Laboratory of Advanced Photonic Materials, Collaborative Innovation Center of Suzhou Nano Science & Technology, and the 111 Project. We thank the BL13SSW beamline at the Shanghai Synchrotron Radiation Facility (https://cstr.cn/31124.02.SSRF. BL13SSW) for the XAFS experiments support. The authors also thank Dr. Xuefei Weng and Dr. Yifan Li for the technical support for Nano-X from Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences, and Dr. Xuchun Wang for data curation.
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Q.Z. and J.C. conceived and supervised the project. W.T. and M.Y.C. carried out the experiments and collected the date. T.Y. and L.Z. contributed to the XAFS measurement and provided analysis. M.X.Z., Q.Q.Z. and X.W. provided the DFT calculation. W.T., M.Y.C. and M.H.C. wrote the manuscript, and M.S.Z., M.X.Z., J.C., and Q.Z. revised it. All the authors contributed to the whole manuscript.
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Tu, W., Chu, M., Yan, T. et al. One-pot co-upcycling of mixed polyolefin waste. Nat Commun (2026). https://doi.org/10.1038/s41467-026-70104-z
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DOI: https://doi.org/10.1038/s41467-026-70104-z
