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Photoelectrochemical CO2-to-fuel conversion with simultaneous plastic reforming


Solar-driven conversion of CO2 and plastics into value-added products provides a potential sustainable route towards a circular economy, but their simultaneous conversion in an integrated process is challenging. Here we introduce a versatile photoelectrochemical platform for CO2 conversion that is coupled to the reforming of plastic. The perovskite-based photocathode enables the integration of different CO2-reduction catalysts such as a molecular cobalt porphyrin, a Cu91In9 alloy and formate dehydrogenase enzyme, which produce CO, syngas and formate, respectively. The Cu27Pd73 alloy anode selectively reforms polyethylene terephthalate plastics into glycolate in alkaline solution. The overall single-light-absorber photoelectrochemical system operates with the help of an internal chemical bias and under zero applied voltage. The system performs similarly to bias-free, dual-light absorber tandems and shows about 10‒100-fold higher production rates than those of photocatalytic suspension processes. This finding demonstrates efficient photoelectrochemical CO2-to-fuel production coupled to plastic-to-chemical conversion as a promising and sustainable technology powered by sunlight.

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Fig. 1: Overview of the PEC set-up demonstrating CO2-to-fuel production coupled with plastic reforming.
Fig. 2: Electrochemical analysis of the catalysts.
Fig. 3: PEC CO2-to-fuel conversion coupled to PET reforming.
Fig. 4: Comparison with representative photocatalytic (PC) and PEC systems.

Data availability

The raw data supporting the findings of this study are available from the University of Cambridge data repository ( Source data are provided with this paper.


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This work was supported by the Cambridge Trust (HRH The Prince of Wales Commonwealth Scholarship to S.B.), the European Commission for Horizon 2020 Marie Skłodowska-Curie Individual European Fellowships (GAN 839763 to M.R. and GAN 891338 to S.R.-J.), the Cambridge Trusts (Vice-Chancellor’s Award to V.A. and Cambridge Thai Foundation Award to C.P.), the Winton Programme for the Physics of Sustainability and St John’s College (Title A Research Fellowship to V.A.), a European Research Council (ERC) Consolidator Grant “MatEnSAP” (682833, to M.M. and E.R.), an EPSRC Impact Acceleration Account Award (to E.L. and E.R.), the UKRI Cambridge Circular Plastics Centre (CirPlas, EP/S025308/1 to E.R.), the Hermann and Marianne Straniak Stiftung (to E.R.) and the Swiss National Science Foundation (Early Postdoc Fellowship P2EZP2_191791 to E.L.). We also acknowledge use of the Cambridge XPS system, part of the Sir Henry Royce Institute (EPSRC grant EP/P024947/1). We are thankful to H. Greer (University of Cambridge) for assistance with the electron microscopy, C. M. Fernández-Posada (University of Cambridge) for assistance with the XPS, A. R. Oliveira and I. A. C. Pereira (ITQB, Universidade Nova de Lisboa) for a sample of FDH as well as S. Linley and S. Kar (University of Cambridge) for useful feedback on the manuscript.

Author information

Authors and Affiliations



S.B., M.R. and E.R. conceived the idea and designed the project. S.B. and M.R. synthesized the bimetallic catalysts, fabricated the (photo)electrodes and carried out all the electrochemical and PEC experiments. V.A. prepared the PVK devices and carried out the EQE experiments. M.M. prepared the IO-TiO2 electrodes and drop-casted the FDH catalyst. S.R.-J. synthesized the CoPL molecular catalyst. S.B. and E.L. performed the density functional theory calculations. C.P. assisted with the catalyst characterization, artwork and schematic diagrams. S.B., M.R. and E.R. co-wrote the manuscript with input from all the co-authors. E.R. supervised the work.

Corresponding author

Correspondence to Erwin Reisner.

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Nature Synthesis thanks Wooseok Yang and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Primary Handling Editor: Alexandra Groves, in collaboration with the Nature Synthesis team.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–16 and Tables 1–6.

Supplementary Video 1

The evolution of CO from a PVK|CoPL photocathode during PEC operation of a Cu27Pd73||PVK|CoPL device with pre-treated PET substrate at the anode.

Source data

Source Data Fig. 2

Raw Data for Fig. 2.

Source Data Fig. 3

Raw Data for Fig. 3.

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Bhattacharjee, S., Rahaman, M., Andrei, V. et al. Photoelectrochemical CO2-to-fuel conversion with simultaneous plastic reforming. Nat. Synth (2023).

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