ABSTRACT The rapidly increasing global demand for energy combined with the environmental impact of fossil fuels has spurred the search for alternative sources of clean energy. One promising

approach is to convert solar energy into hydrogen fuel using photoelectrochemical cells. However, the semiconducting photoelectrodes used in these cells typically have low efficiencies

and/or stabilities. Here we show that a silicon-based photocathode with a capping epitaxial oxide layer can provide efficient and stable hydrogen production from water. In particular, a thin

epitaxial layer of strontium titanate (SrTiO3) was grown directly on Si(001) by molecular beam epitaxy. Photogenerated electrons can be transported easily through this layer because of the

after 35 hours of operation in 0.5 M H2SO4. The performance of the photocathode was also found to be highly dependent on the size and spacing of the structured metal catalyst. Therefore,

mesh-like Ti/Pt nanostructured catalysts were created using a nanosphere lithography lift-off process and an applied-bias photon-to-current efficiency of 4.9% was achieved. Access through

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CONTENT BEING VIEWED BY OTHERS ATOMICALLY DISPERSED IRIDIUM CATALYSTS ON SILICON PHOTOANODE FOR EFFICIENT PHOTOELECTROCHEMICAL WATER SPLITTING Article Open access 04 February 2023 WATER

SPLITTING WITH SILICON P–I–N SUPERLATTICES SUSPENDED IN SOLUTION Article 08 February 2023 DEVELOPMENT OF A PHOTOELECTROCHEMICALLY SELF-IMPROVING SI/GAN PHOTOCATHODE FOR EFFICIENT AND DURABLE

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Download references ACKNOWLEDGEMENTS The authors acknowledge research support from the National Science Foundation (ECCS-1120823 and Award DMR-1207342), the Office of Naval Research (Grant

N00014-10-10489) and the Judson S. Swearingen Regents Chair in Engineering at the University of Texas at Austin. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Electrical and

Computer Engineering, Microelectronics Research Center, University of Texas at Austin, 78712, Texas, USA Li Ji, Xiaohan Li, Haiyu Huang, Jack C. Lee & Edward T. Yu * Department of

Chemistry and Biochemistry, Center for Electrochemistry, University of Texas at Austin, 78712, Texas, USA Li Ji, Shijun Wang & Allen J. Bard * Department of Chemical Engineering,

University of Texas at Austin, 78712, Texas, USA Martin D. McDaniel & John G. Ekerdt * Department of Physics, University of Texas at Austin, 78712, Texas, USA Agham B. Posadas & 

Alexander A. Demkov Authors * Li Ji View author publications You can also search for this author inPubMed Google Scholar * Martin D. McDaniel View author publications You can also search for

this author inPubMed Google Scholar * Shijun Wang View author publications You can also search for this author inPubMed Google Scholar * Agham B. Posadas View author publications You can

also search for this author inPubMed Google Scholar * Xiaohan Li View author publications You can also search for this author inPubMed Google Scholar * Haiyu Huang View author publications

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author publications You can also search for this author inPubMed Google Scholar * Allen J. Bard View author publications You can also search for this author inPubMed Google Scholar * John G.

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Scholar CONTRIBUTIONS L.J., M.D.M., J.G.E. and E.T.Y. contributed to the design concept. L.J., X.L., S.W. and H.H. performed the fabrication process and measurements. M.D.M., A.B.P., A.A.D.

and J.G.E. performed the MBE growth. All authors discussed the results and commented on the manuscript. CORRESPONDING AUTHOR Correspondence to Li Ji. ETHICS DECLARATIONS COMPETING INTERESTS

The authors declare no competing financial interests. SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION Supplementary Information (PDF 642 kb) SUPPLEMENTARY MOVIE 1 Supplementary Movie 1

(AVI 1459 kb) SUPPLEMENTARY MOVIE 2 Supplementary Movie 2 (AVI 1008 kb) RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Ji, L., McDaniel, M., Wang, S.

_et al._ A silicon-based photocathode for water reduction with an epitaxial SrTiO3 protection layer and a nanostructured catalyst. _Nature Nanotech_ 10, 84–90 (2015).

https://doi.org/10.1038/nnano.2014.277 Download citation * Received: 05 May 2014 * Accepted: 22 October 2014 * Published: 01 December 2014 * Issue Date: January 2015 * DOI:

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