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The role of defects and excess surface charges at finite temperature for optimizing oxide photoabsorbers

Nature Materialsvolume 17pages11221127 (2018) | Download Citation


Computational screening of materials for solar to fuel conversion technologies has mostly focused on bulk properties, thus neglecting the structure and chemistry of surfaces and interfaces with water. We report a finite temperature study of WO3, a promising anode for photoelectrochemical cells, carried out using first-principles molecular dynamics simulations coupled with many-body perturbation theory. We identified three major factors determining the chemical reactivity of the material interfaced with water: the presence of surface defects, the dynamics of excess charge at the surface, and finite temperature fluctuations of the surface electronic orbitals. These general descriptors are essential for the understanding and prediction of optimal oxide photoabsorbers for water oxidation.

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This work was supported by the NSF-CCI grant CHE-1305124, using codes developed within the Midwest Integrated Center for Computational Materials (MICCoM) as part of the Computational Materials Sciences Program funded by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), Materials Sciences and Engineering Division. We thank Z.-X. Shen, T. Cuk, T. Lian and Y. Ping for numerous discussions.

Author information


  1. Institute for Molecular Engineering, The University of Chicago, Chicago, Illinois, USA

    • Matteo Gerosa
    • , Marco Govoni
    •  & Giulia Galli
  2. Department of Computer Science, University of California, Davis, Davis, California, USA

    • Francois Gygi
  3. Argonne National Laboratory, Argonne, IL, USA

    • Marco Govoni
    •  & Giulia Galli
  4. Department of Chemistry, The University of Chicago, Chicago, IL, USA

    • Giulia Galli


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Matteo G. and G.G. conceived and designed the calculations. Matteo G. performed the calculations, with numerous discussions with F.G. and Marco G. The manuscript was written primarily by Matteo G. and G.G. All authors discussed the results and commented on the manuscript.

Competing interests

The authors declare no competing interests.

Corresponding author

Correspondence to Giulia Galli.

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