Efficient water oxidation at carbon nanotube–polyoxometalate electrocatalytic interfaces


Water is the renewable, bulk chemical that nature uses to enable carbohydrate production from carbon dioxide. The dream goal of energy research is to transpose this incredibly efficient process and make an artificial device whereby the catalytic splitting of water is finalized to give a continuous production of oxygen and hydrogen. Success in this task would guarantee the generation of hydrogen as a carbon-free fuel to satisfy our energy demands at no environmental cost. Here we show that very efficient and stable nanostructured, oxygen-evolving anodes are obtained by the assembly of an oxygen-evolving polyoxometalate cluster (a totally inorganic ruthenium catalyst) with a conducting bed of multiwalled carbon nanotubes. Our bioinspired electrode addresses the one major challenge of artificial photosynthesis, namely efficient water oxidation, which brings us closer to being able to power the planet with carbon-free fuels.

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Figure 1: Nanostructured oxygen-evolving material.
Figure 2: Characterization of the composite 1@MWCNT.
Figure 3: Electroactive nanostructured ITO anodes.


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We thank M. Meneghetti for assistance with the RAMAN spectroscopy and discussion of the data. Financial support from Consiglio Nazionale delle Ricerche (CNR), Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM), Ministero dell'Istruzione, dell'Università e della Ricerca (MIUR, PRIN Contract No. 20085M27SS), University of Padova (Progetto Strategico 2008, HELIOS, prot. STPD08RCX) the European Science Foundation's Cooperation in Science and Technology D40 action, Fondazione Cassa di Risparmio in Bologna and the University of Bologna is acknowledged.

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F.M.T. performed the synthetic tasks, optimized the deposition protocol and coordinated the characterization and electrocatalytic experiments; A.S. and M.C. contributed to the design, synthesis and characterization of the POM interface; C.M. carried out the SEM and AFM, and analysed the data; B.R.G. performed the HRTEM and STEM analyses; H.A. carried out the SAXS and analysed the data; L.C., A.G. and P.P. performed the XPS and analysed the data; F.P., M.M., S.R. and M.I. performed and analysed the electrochemistry experiments; T.D.R. discussed and supervised the functionalization of carbon nanostructure; G. Scorrano helped with the design and discussion of the experiments; G. Scoles helped with the design and discussion of the experiments, and contributed to writing the manuscript; M.P. and M.B. planned and supervised the research, analysed the data and co-wrote the manuscript.

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Correspondence to Maurizio Prato or Marcella Bonchio.

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Toma, F., Sartorel, A., Iurlo, M. et al. Efficient water oxidation at carbon nanotube–polyoxometalate electrocatalytic interfaces. Nature Chem 2, 826–831 (2010). https://doi.org/10.1038/nchem.761

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