Bias-free solar syngas production by integrating a molecular cobalt catalyst with perovskite–bivo4 tandems

ABSTRACT The photoelectrochemical (PEC) production of syngas from water and CO2 represents an attractive technology towards a circular carbon economy. However, the high overpotential, low

selectivity and cost of commonly employed catalysts pose challenges for this sustainable energy-conversion process. Here we demonstrate highly tunable PEC syngas production by integrating a

cobalt porphyrin catalyst immobilized on carbon nanotubes with triple-cation mixed halide perovskite and BiVO4 photoabsorbers. Empirical data analysis is used to clarify the optimal

electrode selectivity at low catalyst loadings. The perovskite photocathodes maintain selective aqueous CO2 reduction for one day at light intensities as low as 0.1 sun, which provides

pathways to maximize daylight utilization by operating even under low solar irradiance. Under 1 sun irradiation, the perovskite–BiVO4 PEC tandems sustain bias-free syngas production coupled

to water oxidation for three days. The devices present solar-to-H2 and solar-to-CO conversion efficiencies of 0.06 and 0.02%, respectively, and are able to operate as standalone artificial

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SIMILAR CONTENT BEING VIEWED BY OTHERS LONG-TERM SOLAR WATER AND CO2 SPLITTING WITH PHOTOELECTROCHEMICAL BIOI–BIVO4 TANDEMS Article 26 May 2022 FLOATING PEROVSKITE-BIVO4 DEVICES FOR SCALABLE

SOLAR FUEL PRODUCTION Article 17 August 2022 SOLAR-DRIVEN LIQUID MULTI-CARBON FUEL PRODUCTION USING A STANDALONE PEROVSKITE–BIVO4 ARTIFICIAL LEAF Article 18 May 2023 DATA AVAILABILITY The

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Solar Syngas Production by Integrating a Molecular Cobalt Catalyst with Perovskite–BiVO_ _4_ _T__andems_ (2019); https://doi.org/10.17863/CAM.44164 Download references ACKNOWLEDGEMENTS This

work was supported by the Christian Doppler Research Association (Austrian Federal Ministry for Digital and Economic Affairs and the National Foundation for Research, Technology and

Development) and the OMV Group (E.R.). V.A. is grateful for the financial support from the Cambridge Trusts (Vice-Chancellor’s Award) and the Winton Programme for the Physics of

Sustainability. B.R. was supported by the BBSRC (grant no. BB/K010220/1). XPS data collection was performed at the EPSRC National Facility for Photoelectron spectroscopy (‘HarwellXPS’),

operated by Cardiff University and UCL under contract no. PR16195. We acknowledge D. S. Wright (University of Cambridge) for providing us the Co WOC precursor. We thank A. Dickerson

(University of Cambridge) for the ICP-OES measurements. We are grateful to D. Achilleos (University of Cambridge) for help with XPS sample preparation and data analysis. We thank K. P. Sokol

(University of Cambridge) for helpful advice on the O2 measurements, and K. P. Sokol and A. Wagner (University of Cambridge) for useful feedback on the manuscript. AUTHOR INFORMATION

AUTHORS AND AFFILIATIONS * Christian Doppler Laboratory for Sustainable SynGas Chemistry, Department of Chemistry, University of Cambridge, Cambridge, UK Virgil Andrei, Bertrand Reuillard 

& Erwin Reisner Authors * Virgil Andrei View author publications You can also search for this author inPubMed Google Scholar * Bertrand Reuillard View author publications You can also

search for this author inPubMed Google Scholar * Erwin Reisner View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS V.A., B.R. and E.R. designed

the project. V.A. prepared the photoelectrodes, performed the experiments and drafted the manuscript. V.A., B.R. and E.R. analysed the data. B.R. and E.R. contributed to the discussion and

completion of the manuscript. E.R. supervised the work. CORRESPONDING AUTHOR Correspondence to Erwin Reisner. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing

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ARTICLE CITE THIS ARTICLE Andrei, V., Reuillard, B. & Reisner, E. Bias-free solar syngas production by integrating a molecular cobalt catalyst with perovskite–BiVO4 tandems. _Nat.

Mater._ 19, 189–194 (2020). https://doi.org/10.1038/s41563-019-0501-6 Download citation * Received: 29 March 2019 * Accepted: 05 September 2019 * Published: 21 October 2019 * Issue Date:

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