There is significant interest in the development of methods to create hybrid materials that transform capabilities, in particular for Earth-abundant metal oxides, such as TiO2, to give improved or new properties relevant to a broad spectrum of applications. Here we introduce an approach we refer to as ‘molecular cross-linking’, whereby a hybrid molecular boron oxide material is formed from polyhedral boron-cluster precursors of the type [B12(OH)12]2–. This new approach is enabled by the inherent robustness of the boron-cluster molecular building block, which is compatible with the harsh thermal and oxidizing conditions that are necessary for the synthesis of many metal oxides. In this work, using a battery of experimental techniques and materials simulation, we show how this material can be interfaced successfully with TiO2 and other metal oxides to give boron-rich hybrid materials with intriguing photophysical and electrochemical properties.

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Change history

  • Correction 16 March 2018

    In the version of this Article originally published, Liban M. A. Saleh was incorrectly listed as Liban A. M. Saleh due to a technical error. This has now been amended in all online versions of the Article.


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A.M.S. thanks the University of California, Los Angeles (UCLA), Department of Chemistry and Biochemistry for start-up funds, 3M for a Non-Tenured Faculty Award and the Alfred P. Sloan Foundation for a research fellowship in chemistry. The authors thank the MRI program of the National Science Foundation (NSF grant no. 1532232 and no.1625776) for sponsoring the acquisition of SSNMR equipment and SQUID, respectively, at UCLA. Z.J.B. was supported by a grant from the BASF Corporation, and the solid-state MAS NMR measurements at the University of California, Santa Barbara (UCSB), made use of the shared facilities of the UCSB MRSEC (NSF DMR 1720256), a member of the Materials Research Facilities Network (www.mrfn.org). E.C.W. and J.T.M. were supported by the National Science Foundation Energy Research Center for Innovative and Strategic Transformations of Alkane Resources (CISTAR) under the cooperative agreement no. EEC-1647722. J.I.Z. thanks the Student and Research Support Fund for financial support. The computational modelling benefited from access to the Extreme Science and Engineering Discovery Environment, which is supported by NSF Grant ACI-1053575. R.R.L. and M.D. were supported by the US Department of Energy (DOE), Office of Basic Energy Sciences, Division of Chemical Sciences, Biosciences and Geosciences under Contract DE-AC02-06CH11357. This research used resources of the APS, a US DOE Office of Basic Energy Sciences and Office of Science User Facility, operated for the DOE Office of Science by Argonne National Laboratory under contract no. DE-AC02-06CH11357. MRCAT operations, beamline 10-BM, are supported by the DOE and the MRCAT member institutions.

Author information


  1. Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA

    • Dahee Jung
    • , Liban M. A. Saleh
    • , Maher F. El-Kady
    • , Jee Youn Hwang
    • , Nahla Mohamed
    • , Alex I. Wixtrom
    • , Ekaterina Titarenko
    • , Yanwu Shao
    • , Kassandra McCarthy
    • , Ignacio B. Martini
    • , Philippe Saint-Cricq
    • , Bastian Ruehle
    • , Jonathan L. Brosmer
    • , Marcus Gallagher-Jones
    • , Jose Rodriguez
    • , Xiangfeng Duan
    • , Richard B. Kaner
    • , Jeffrey I. Zink
    •  & Alexander M. Spokoyny
  2. California NanoSystems Institute (CNSI), University of California, Los Angeles, Los Angeles, CA, USA

    • Dahee Jung
    • , Maher F. El-Kady
    • , Marcus Gallagher-Jones
    • , Jose Rodriguez
    • , Xiangfeng Duan
    • , Richard B. Kaner
    • , Jeffrey I. Zink
    •  & Alexander M. Spokoyny
  3. Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, CA, USA

    • Zachariah J. Berkson
    •  & Bradley F. Chmelka
  4. Department of Chemistry, Faculty of Science, Cairo University, Giza, Egypt

    • Nahla Mohamed
  5. Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, USA

    • Jian Guo
    •  & Richard B. Kaner
  6. Materials Research Center, University of California, Santa Barbara, Santa Barbara, CA, USA

    • Stephan Kraemer
  7. Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN, USA

    • Evan C. Wegener
    •  & Jeffrey T. Miller
  8. Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, IL, USA

    • Ryan R. Langeslay
    •  & Massimiliano Delferro
  9. Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, USA

    • Christopher H. Hendon
  10. X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA

    • Karena W. Chapman


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A.M.S. developed the concept of molecular cross-linking and supervised the project. D.J., L.M.A.S. and A.M.S. co-designed the experiments, D.J. and L.M.A.S. performed the synthetic experimental work and D.J. performed the majority of the structural characterization and data analysis. Z.J.B. and B.F.C. designed, conducted and interpreted the SSNMR experiments and data. M.F.E.-K., J.Y.H. and, N.M. performed the electrochemical studies and interpreted the data with R.B.K. D.J., L.M.A.S., E.T., Y.S. and K.M. performed the dye degradation experiments. A.I.W. performed the EPR measurements. J.G. performed the resistivity measurements and interpreted the data with X.D. I.B.M. performed the SQUID measurements. S.K. designed and performed the STEM measurements. E.C.W. performed the XANES and EXAFS measurements and analysed the data with J.T.M. P.S.-C. and B.R. performed the mechanistic photochemical work and analysed the data with J.I.Z. R.R.L. and M.D. performed the TGA–MS and TPD ammonia experiments. J.L.B. performed the Raman spectroscopic measurements. C.H.H. performed the computational modelling. M.G.-J. and J.R. performed the TEM measurements and created the 3D reconstruction. K.W.C. collected and interpreted the high-energy X-ray scattering data . D.J., L.M.A.S., A.M.S., Z.J.B. and B.F.C. co-wrote the manuscript. All the authors discussed the results and commented on the manuscript during its preparation.

Competing financial interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Alexander M. Spokoyny.

Supplementary information

  1. Supplementary Information

    Supplementary Figures 1–58, Supplementary Tables 1–4, Supplementary References 1–12