Plasmon resonant enhancement of photocatalytic water splitting under visible illumination.

We demonstrate plasmonic enhancement of photocatalytic water splitting under visible illumination by integrating strongly plasmonic Au nanoparticles with strongly catalytic TiO2. Under visible illumination, we observe enhancements of up to 66× in the photocatalytic splitting of water in TiO2 with the addition of Au nanoparticles. Above the plasmon resonance, under ultraviolet radiation we observe a 4-fold reduction in the photocatalytic activity. Electromagnetic simulations indicate that the improvement of photocatalytic activity in the visible range is caused by the local electric field enhancement near the TiO2 surface, rather than by the direct transfer of charge between the two materials. Here, the near-field optical enhancement increases the electron-hole pair generation rate at the surface of the TiO2, thus increasing the amount of photogenerated charge contributing to catalysis. This mechanism of enhancement is particularly effective because of the relatively short exciton diffusion length (or minority carrier diffusion length), which otherwise limits the photocatalytic performance. Our results suggest that enhancement factors many times larger than this are possible if this mechanism can be optimized.

[1]  Baozhu Tian,et al.  Comparative studies of operational parameters of degradation of azo dyes in visible light by highly efficient WOx/TiO2 photocatalyst. , 2010, Journal of hazardous materials.

[2]  S. Linic,et al.  Enhancing Photochemical Activity of Semiconductor Nanoparticles with Optically Active Ag Nanostructures: Photochemistry Mediated by Ag Surface Plasmons , 2010 .

[3]  S. Cronin,et al.  Plasmon resonant enhancement of carbon monoxide catalysis. , 2010, Nano letters.

[4]  Wei Hsuan Hung,et al.  Optical manipulation of plasmonic nanoparticles, bubble formation and patterning of SERS aggregates , 2010, Nanotechnology.

[5]  J. Durrant,et al.  Electron Diffusion Length in Mesoporous Nanocrystalline TiO2 Photoelectrodes during Water Oxidation , 2010 .

[6]  Ewa Kowalska,et al.  Visible-light-induced photocatalysis through surface plasmon excitation of gold on titania surfaces. , 2010, Physical chemistry chemical physics : PCCP.

[7]  Lukas Novotny,et al.  Surface-enhanced nonlinear four-wave mixing. , 2010, Physical review letters.

[8]  J. R. Adleman,et al.  Heterogenous catalysis mediated by plasmon heating. , 2009, Nano letters.

[9]  Qi Li,et al.  Self-organized nitrogen and fluorine co-doped titanium oxide nanotube arrays with enhanced visible light photocatalytic performance. , 2009, Environmental science & technology.

[10]  M. El-Sayed,et al.  Plasmonic Field Effect on the Hexacyanoferrate (III)-Thiosulfate Electron Transfer Catalytic Reaction on Gold Nanoparticles: Electromagnetic or Thermal? , 2009 .

[11]  S. Cronin,et al.  Iterative optimization of plasmon resonant nanostructures , 2009 .

[12]  Mark L Brongersma,et al.  Plasmon-enhanced emission from optically-doped MOS light sources. , 2009, Optics express.

[13]  Harry A. Atwater,et al.  Plasmonic nanoparticle enhanced light absorption in GaAs solar cells , 2008 .

[14]  S. Cronin,et al.  Laser directed growth of carbon-based nanostructures by plasmon resonant chemical vapor deposition. , 2008, Nano letters.

[15]  Javier Aizpurua,et al.  Metallic nanoparticle arrays: a common substrate for both surface-enhanced Raman scattering and surface-enhanced infrared absorption. , 2008, ACS nano.

[16]  Carsten Rockstuhl,et al.  A plasmonic photocatalyst consisting of silver nanoparticles embedded in titanium dioxide. , 2008, Journal of the American Chemical Society.

[17]  S. Cronin,et al.  Surface-enhanced Raman spectroscopy and correlated scanning electron microscopy of individual carbon nanotubes , 2007 .

[18]  Remy Cromer,et al.  SERS nanoparticles: a new optical detection modality for cancer diagnosis. , 2007, Nanomedicine.

[19]  L. Greengard,et al.  Plasmon-assisted chemical vapor deposition. , 2006, Nano letters.

[20]  Tatsuro Endo,et al.  Multiple label-free detection of antigen-antibody reaction using localized surface plasmon resonance-based core-shell structured nanoparticle layer nanochip. , 2006, Analytical chemistry.

[21]  X. Wang,et al.  Wavelength-sensitive photocatalytic degradation of methyl orange in aqueous suspension over iron(III)-doped TiO2 nanopowders under UV and visible light irradiation. , 2006, The journal of physical chemistry. B.

[22]  H. Fu,et al.  Preparation of large-pore mesoporous nanocrystalline TiO2 thin films with tailored pore diameters. , 2005, The journal of physical chemistry. B.

[23]  Tetsu Tatsuma,et al.  Mechanisms and applications of plasmon-induced charge separation at TiO2 films loaded with gold nanoparticles. , 2005, Journal of the American Chemical Society.

[24]  P. Nordlander,et al.  Finite-difference time-domain studies of the optical properties of nanoshell dimers. , 2005, The journal of physical chemistry. B.

[25]  George C. Schatz,et al.  Silver nanoparticle array structures that produce giant enhancements in electromagnetic fields , 2005 .

[26]  Tetsu Tatsuma,et al.  Plasmon-induced photoelectrochemistry at metal nanoparticles supported on nanoporous TiO2. , 2004, Chemical communications.

[27]  M. Antonietti,et al.  Highly crystalline cubic mesoporous TiO₂ with 10-nm pore diameter made with a new block copolymer template , 2004 .

[28]  G. Schatz,et al.  Electromagnetic fields around silver nanoparticles and dimers. , 2004, The Journal of chemical physics.

[29]  Louis E. Brus,et al.  Single Molecule Raman Spectroscopy at the Junctions of Large Ag Nanocrystals , 2003 .

[30]  Craig A. Grimes,et al.  Crystallization and high-temperature structural stability of titanium oxide nanotube arrays , 2003 .

[31]  A. Requicha,et al.  Plasmonics—A Route to Nanoscale Optical Devices , 2001 .

[32]  Michael Grätzel,et al.  Photoelectrochemical cells , 2001, Nature.

[33]  Hans-Heinrich Hörhold,et al.  Efficient Titanium Oxide/Conjugated Polymer Photovoltaics for Solar Energy Conversion , 2000 .

[34]  M. Anpo,et al.  Photocatalytic decomposition of NO under visible light irradiation on the Cr‐ion‐implanted TiO2 thin film photocatalyst , 2000 .

[35]  H. Takikawa,et al.  Structural and optical properties of titanium oxide thin films deposited by filtered arc deposition , 1999 .

[36]  Tom J. Savenije,et al.  Visible light sensitisation of titanium dioxide using a phenylene vinylene polymer , 1998 .

[37]  R. Dasari,et al.  Single Molecule Detection Using Surface-Enhanced Raman Scattering (SERS) , 1997 .

[38]  N. Serpone,et al.  Size Effects on the Photophysical Properties of Colloidal Anatase TiO2 Particles: Size Quantization versus Direct Transitions in This Indirect Semiconductor? , 1995 .

[39]  Allen Taflove,et al.  Computational Electrodynamics the Finite-Difference Time-Domain Method , 1995 .

[40]  R. V. Duyne,et al.  Atomic force microscopy and surface-enhanced Raman spectroscopy. I. Ag island films and Ag film over polymer nanosphere surfaces supported on glass , 1993 .

[41]  D. L. Jeanmaire,et al.  Surface raman spectroelectrochemistry: Part I. Heterocyclic, aromatic, and aliphatic amines adsorbed on the anodized silver electrode , 1977 .