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Ambient solar thermal catalysis for polyolefin upcycling using copper encapsulated in silicon nanosheets and chloroaluminate ionic liquid

Nature Catalysis volume 8, pages 556–568 (2025)Cite this article

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Abstract

The accumulation of plastic waste has become a global issue. Socially and industrially viable, sustainable technical solutions are therefore required. Here we report a solar thermal catalytic system for polyolefins upcycling using copper nanoparticles encapsulated by stacked two-dimensional silicon. In a chloroaluminate ionic liquid solvent, unlike conventional thermal techniques, the upcycling can proceed under a mild temperature (55 °C) created photothermally under 4 sun irradiation. The polyethylene can be completely transformed into distinct and separable fractions of alkanes (C3–C7) and cyclic hydrocarbons (C8–C26) within hours, with a total yield of 91%. Mechanistic studies show a pathway involved two β-scissions of C–C bonds and a rapid cyclization. The approach offers versatility in the upcycling of various real-world polyolefin waste and features excellent feasibility in outdoor practices. The analyses of a conceptual upcycling facility using this technology showcase its appeal in both economic and eco-friendliness.

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Fig. 1: Schematic preparation and characterization of Cu/2D Si catalyst.
Fig. 2: Performance and proposed reaction pathways for solar thermal catalytic plastic upcycling.
Fig. 3: Function of Cu NPs and 2D Si in solar thermal catalytic plastic upcycling.
Fig. 4: Function of light in solar thermal catalytic plastic upcycling.
Fig. 5: Robustness and demonstrations of solar thermal catalytic plastic upcycling system.

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The datasets generated during and/or analysed during the study are provided with this paper or available from the authors on reasonable request. Source Data are provided with this paper.

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Acknowledgements

The project was supported by the National Key R&D Program of China (2021YFF0502000), the U of T-ZJU Joint Seed Fund, the Fundamental Research Funds for the Central Universities, China (226-2022-00200). Many thanks to G. Vezina of Hydrofuel Canada Inc., the Natural Sciences and Engineering Research Council of Canada (NSERC) for financial support. This work was also supported by the Natural Science Foundation of China (72374135), the Shanghai Rising-Star Program (23QA1404900), and the Natural Science Foundation of Shanghai (23ZR1434100).

Author information

Author notes

  1. These authors contributed equally: Chuanwang Xing, Chengliang Mao.

Authors and Affiliations

  1. State Key Laboratory of Silicon and Advanced Semiconductor Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, China

    Chuanwang Xing, Shenghua Wang, Dake Zhang, Dingxuan Kang, Deren Yang & Wei Sun

  2. Materials Chemistry and Nanochemistry Research Group, Solar Fuels Cluster, Departments of Chemistry, University of Toronto, Toronto, Ontario, Canada

    Chengliang Mao, Lei Wu & Geoffrey A. Ozin

  3. State Key Laboratory of Green Papermaking and Resource Recycling, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China

    Chengliang Mao, Di Yang, Weiting Gong & Wendong Wei

  4. Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, China

    Yuxuan Zhou & Chaoran Li

  5. Key Lab of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China

    Liang Wang

  6. Institute of Advanced Semiconductors & Zhejiang Provincial Key Laboratory of Power Semiconductor Materials and Devices, Hangzhou Global Scientific and Technological Innovation Center, Hangzhou, China

    Deren Yang

  7. Shangyu Institute of Semiconductor Materials, Shaoxing, China

    Wei Sun

Authors
  1. Chuanwang Xing
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Contributions

C.X., S.W., W.S. and G.A.O conceived and designed the experiments. C.X., L. Wu and S.W. peformed the synthesis experiments. C.X., D.Z. and D.K. performed the structural characterization of catalysts. C.X., W.S. performed and analysed the catalytic experiments. With the support of L. Wang, C.X. performed the hydrogenation experiments. Y.Z. and C.L. performed the heat transfer stimulation. C.X., C.M., Di Yang, W.G. and W.W. conducted the techno-economic analysis. C.X., W.S., C.M., Deren Yang and G.A.O. wrote the paper. W.S., G.A.O and Deren Yang supervised the project. All authors commented on the final paper.

Corresponding authors

Correspondence to Geoffrey A. Ozin, Deren Yang or Wei Sun.

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Competing interests

A Chinese patent application (application no. 202410188427.2; Inventors: W.S., C.X., Deren.Y.) and a United States patent application (application no. 19057203; Inventors: W.S., C.X., G.A.O., Deren.Y.) related to part of this work are currently under examination. The other authors declare no competing interests.

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Nature Catalysis thanks Kevin van Geem for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary Notes 1–6, Figs. 1–48 and Tables 1–11.

Supplementary Table 1

Automatic qualitative identifications of upcycling products measured by 2D gas chromatography with mass spectrometry.

Source data

Source Data Fig. 1

Statistical source data of Fig. 1.

Source Data Fig. 2

Statistical source data of Fig. 2.

Source Data Fig. 3

Statistical source data of Fig. 3.

Source Data Fig. 4

Statistical source data of Fig. 4.

Source Data Fig. 5

Statistical source data of Fig. 5.

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Xing, C., Mao, C., Wang, S. et al. Ambient solar thermal catalysis for polyolefin upcycling using copper encapsulated in silicon nanosheets and chloroaluminate ionic liquid. Nat Catal 8, 556–568 (2025). https://doi.org/10.1038/s41929-025-01349-y

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