3D branched nanowire heterojunction photoelectrodes for high-efficiency solar water splitting and H2 generation.

We report the fabrication of a three dimensional branched ZnO/Si heterojunction nanowire array by a two-step, wafer-scale, low-cost, solution etching/growth method and its use as photoelectrode in a photoelectrochemical cell for high efficiency solar powered water splitting. Specifically, we demonstrate that the branched nanowire heterojunction photoelectrode offers improved light absorption, increased photocurrent generation due to the effective charge separation in Si nanowire backbones and ZnO nanowire branching, and enhanced gas evolution kinetics because of the dramatically increased surface area and decreased radius of curvature. The branching nanowire heterostructures offer direct functional integration of different materials for high efficiency water photoelectrolysis and scalable photoelectrodes for clean hydrogen fuel generation.

[1]  Jian Shi,et al.  Three-dimensional high-density hierarchical nanowire architecture for high-performance photoelectrochemical electrodes. , 2011, Nano letters.

[2]  Yohan Park,et al.  Atomic layer-deposited tunnel oxide stabilizes silicon photoanodes for water oxidation. , 2011, Nature materials.

[3]  K. Sun,et al.  Compound Semiconductor Nanowire Solar Cells , 2011, IEEE Journal of Selected Topics in Quantum Electronics.

[4]  Chun Xing Li,et al.  Solution synthesis of large-scale, high-sensitivity ZnO/Si hierarchical nanoheterostructure photodetectors. , 2010, Journal of the American Chemical Society.

[5]  H. Matthews,et al.  Future CO2 Emissions and Climate Change from Existing Energy Infrastructure , 2010, Science.

[6]  M. I. Hoffert,et al.  Farewell to Fossil Fuels? , 2010, Science.

[7]  Junyou Yang,et al.  Coaxial heterogeneous structure of TiO2 nanotube arrays with CdS as a superthin coating synthesized via modified electrochemical atomic layer deposition. , 2010, Journal of the American Chemical Society.

[8]  Xin Wang,et al.  High-performance silicon nanohole solar cells. , 2010, Journal of the American Chemical Society.

[9]  K. Sunahara,et al.  Femtosecond diffuse reflectance transient absorption for dye-sensitized solar cells under operational conditions: effect of electrolyte on electron injection. , 2010, Journal of the American Chemical Society.

[10]  Nathan S Lewis,et al.  Enhanced absorption and carrier collection in Si wire arrays for photovoltaic applications. , 2010, Nature materials.

[11]  Peidong Yang,et al.  Light trapping in silicon nanowire solar cells. , 2010, Nano letters.

[12]  Jennifer K. Hensel,et al.  Synergistic effect of CdSe quantum dot sensitization and nitrogen doping of TiO(2) nanostructures for photoelectrochemical solar hydrogen generation. , 2010, Nano letters.

[13]  Nathan S. Lewis,et al.  Energy-Conversion Properties of Vapor-Liquid-Solid–Grown Silicon Wire-Array Photocathodes , 2010, Science.

[14]  Jennifer K. Hensel,et al.  Preparation and Photoelectrochemical Properties of CdSe/TiO 2 Hybrid Mesoporous Structures , 2010 .

[15]  Dunwei Wang,et al.  Synthesis and photoelectrochemical study of vertically aligned silicon nanowire arrays. , 2009, Angewandte Chemie.

[16]  Yat Li,et al.  Hydrogen generation from photoelectrochemical water splitting based on nanomaterials , 2009 .

[17]  Yun Jeong Hwang,et al.  High density n-Si/n-TiO2 core/shell nanowire arrays with enhanced photoactivity. , 2009, Nano letters.

[18]  Yiping Zhao,et al.  Photoelectrochemical Study of Nanostructured ZnO Thin Films for Hydrogen Generation from Water Splitting , 2009 .

[19]  Michael Grätzel,et al.  WO3-Fe2O3 Photoanodes for Water Splitting: A Host Scaffold, Guest Absorber Approach , 2009 .

[20]  Jianwei Sun,et al.  Solar water oxidation by composite catalyst/alpha-Fe(2)O(3) photoanodes. , 2009, Journal of the American Chemical Society.

[21]  Wilson A. Smith,et al.  Superior photocatalytic performance by vertically aligned core–shell TiO2/WO3 nanorod arrays , 2009 .

[22]  Stafford W. Sheehan,et al.  TiO(2)/TiSi(2) heterostructures for high-efficiency photoelectrochemical H(2)O splitting. , 2009, Journal of the American Chemical Society.

[23]  Baozeng Guo,et al.  Electrical properties and carrier transport mechanisms of n-ZnO/SiOx/n-Si isotype heterojunctions with native or thermal oxide interlayers , 2009 .

[24]  Wilson A. Smith,et al.  Enhanced Photocatalytic Activity by Aligned WO3/TiO2 Two-Layer Nanorod Arrays , 2008 .

[25]  T. Mallouk,et al.  Effect of twinning on the photoluminescence and photoelectrochemical properties of indium phosphide nanowires grown on silicon (111). , 2008, Nano letters (Print).

[26]  Qing Chen,et al.  CdS quantum dots sensitized TiO2 nanotube-array photoelectrodes. , 2008, Journal of the American Chemical Society.

[27]  C. Pan,et al.  Improved broadband and quasi-omnidirectional anti-reflection properties with biomimetic silicon nanostructures. , 2007, Nature nanotechnology.

[28]  Charles M. Lieber,et al.  Coaxial silicon nanowires as solar cells and nanoelectronic power sources , 2007, Nature.

[29]  Gang Chen,et al.  Analysis of optical absorption in silicon nanowire arrays for photovoltaic applications. , 2007, Nano letters.

[30]  Kok-Keong Lew,et al.  Silicon nanowire array photelectrochemical cells. , 2007, Journal of the American Chemical Society.

[31]  Rakesh Agrawal,et al.  Sustainable fuel for the transportation sector , 2007, Proceedings of the National Academy of Sciences.

[32]  C. Soci,et al.  ZnO nanowire UV photodetectors with high internal gain. , 2007, Nano letters.

[33]  N. Lewis.  Toward Cost-Effective Solar Energy Use , 2007, Science.

[34]  Michael Grätzel,et al.  New Benchmark for Water Photooxidation by Nanostructured α-Fe2O3 Films , 2006 .

[35]  Yu Hang Leung,et al.  Optical properties of ZnO nanostructures. , 2006, Small.

[36]  S. Polasky,et al.  Environmental, economic, and energetic costs and benefits of biodiesel and ethanol biofuels. , 2006, Proceedings of the National Academy of Sciences of the United States of America.

[37]  Michael Grätzel,et al.  Translucent thin film Fe2O3 photoanodes for efficient water splitting by sunlight: nanostructure-directing effect of Si-doping. , 2006, Journal of the American Chemical Society.

[38]  Yin Wu,et al.  Uniform, axial-orientation alignment of one-dimensional single-crystal silicon nanostructure arrays. , 2005, Angewandte Chemie.

[39]  Peidong Yang,et al.  Low-temperature wafer-scale production of ZnO nanowire arrays. , 2003, Angewandte Chemie.

[40]  L. Vayssieres.  Growth of Arrayed Nanorods and Nanowires of ZnO from Aqueous Solutions , 2003 .

[41]  S. T. Lee,et al.  Small-Diameter Silicon Nanowire Surfaces , 2003, Science.

[42]  Yunjie Yan,et al.  Dendrite‐Assisted Growth of Silicon Nanowires in Electroless Metal Deposition , 2003 .

[43]  H. Yeom,et al.  Optimum Thickness of SiO2 Layer Formed at the Interface of N-ZnO/P-Si Photodiodes , 2002 .

[44]  W. Ingler,et al.  Efficient Photochemical Water Splitting by a Chemically Modified n-TiO2 , 2002, Science.

[45]  Yunjie Yan,et al.  Synthesis of Large‐Area Silicon Nanowire Arrays via Self‐Assembling Nanoelectrochemistry , 2002 .

[46]  Hoi Sing Kwok,et al.  OPTICAL PROPERTIES OF EPITAXIALLY GROWN ZINC OXIDE FILMS ON SAPPHIRE BY PULSED LASER DEPOSITION , 1999 .

[47]  Turner,et al.  A monolithic photovoltaic-photoelectrochemical device for hydrogen production via water splitting , 1998, Science.

[48]  D. Lincot,et al.  Investigation of the influence of the electrodeposition potential on the optical, photoelectrochemical and structural properties of as-deposited CdTe , 1995 .

[49]  J. Bockris,et al.  Photoelectrochemical evolution of hydrogen on p-indium phosphide , 1984 .

[50]  A. Heller.  Hydrogen-Evolving Solar Cells , 1984, Science.

[51]  N. Lewis,et al.  Synthesis and characterization of a photosensitive interface for hydrogen generation: Chemically modified p-type semiconducting silicon photocathodes. , 1980, Proceedings of the National Academy of Sciences of the United States of America.

[52]  N. Lewis,et al.  Photoreduction at illuminated p-type semiconducting silicon photoelectrodes. Evidence for Fermi level pinning , 1980 .

[53]  N. Lewis,et al.  Photoelectrochemical reduction of N,N'-dimethyl-4,4'-bipyridinium in aqueous media at p-type silicon: sustained photogeneration of a species capable of evolving hydrogen , 1979 .

[54]  Lord Rayleigh,et al.  On Reflection of Vibrations at the Confines of two Media between which the Transition is Gradual , 1879 .

[55]  Zongfu Yu,et al.  Optical absorption enhancement in amorphous silicon nanowire and nanocone arrays. , 2009, Nano letters.

[56]  Charles M. Lieber,et al.  High Performance Silicon Nanowire Field Effect Transistors , 2003 .

[57]  M. Grätzel.  Photoelectrochemical cells : Materials for clean energy , 2001 .

[58]  M. Green,et al.  Optical properties of intrinsic silicon at 300 K , 1995 .

[59]  Y. W. Chen,et al.  n-CuInSe2 photoelectrochemical cells , 1986 .

[60]  N. Lewis,et al.  Improvement of photoelectrochemical hydrogen generation by surface modification of p-type silicon semiconductor photocathodes , 1982 .