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Nanotechnology makes biomass electrolysis more energy efficient than water electrolysis

Nature Communications volume 5, Article number: 4036 (2014) | Download Citation


The energetic convenience of electrolytic water splitting is limited by thermodynamics. Consequently, significant levels of hydrogen production can only be obtained with an electrical energy consumption exceeding 45kWhkg-1H2. Electrochemical reforming allows the overcoming of such thermodynamic limitations by replacing oxygen evolution with the oxidation of biomass-derived alcohols. Here we show that the use of an original anode material consisting of palladium nanoparticles deposited on to a three-dimensional architecture of titania nanotubes allows electrical energy savings up to 26.5kWhkg-1H2 as compared with proton electrolyte membrane water electrolysis. A net energy analysis shows that for bio-ethanol with energy return of the invested energy larger than 5.1 (for example, cellulose), the electrochemical reforming energy balance is advantageous over proton electrolyte membrane water electrolysis.

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We gratefully acknowledge the European Union for the collaborative project ‘DECORE’ COOPERATION FP7-NMP-2012-SMALL-6nmp4-sl-2012-309741 and the Ente Cassa di Risparmio di Firenze for the project HYDROLAB. We are grateful to the ICCOM CNR workshop technician Mr Carlo Bartoli for having built the hardware for the electrochemical reforming employed in this work. We also acknowledge Mr Fabio Migliacci for the kind support in arranging the artwork related to the paper.

Author information


  1. ICCOM-CNR, via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy

    • Y. X. Chen
    • , A. Lavacchi
    • , H. A. Miller
    • , M. Bevilacqua
    • , J. Filippi
    • , M. Innocenti
    • , A. Marchionni
    • , W. Oberhauser
    • , L. Wang
    •  & F. Vizza
  2. Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127 Trieste, Italy

    • Y. X. Chen
    •  & L. Wang
  3. Dipartimento di Chimica, Università di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy

    • M. Innocenti


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Y.X.C. did most of the experimental work including material synthesis, most of the scanning electron microscopic observation and the electrochemical characterization of the catalysts. A.L. ideated the work, supervised the research and wrote most of the paper. He also performed net energy calculations. H.A.M. performed the electrolysis experiments and provided a significant contribution to the paper writing. M.B. performed part of the electrochemical characterization of the catalysts including active surface area measurements. J.F. performed part of the electrochemical characterization of the catalysts including active surface area measurements. M.I. helped to define the protocols for assessing the surface area of palladium also providing active support to the interpretation of electron microscopy material characterization. A.M. performed the chemical analysis of the anode electrolyte after the experiments to assess selectivity. W.O. performed the X-ray diffraction experiments and contributed to the plane assignment in the HRTEM images. L.W. performed the synthesis of cathode materials and investigated the assembly of the 3D TNTA architectures into membrane electrode assemblies. F.V. supervised the work contributing to the paper writing and to define the experimental protocols for the electrolysis measurements.

Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to A. Lavacchi or F. Vizza.

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    Supplementary Figures 1-5, Supplementary Table 1, Supplementary Note 1 and Supplementary Methods

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