Hedgehog-like hierarchical ZnO needle-clusters with superior electron transfer kinetics for dye-sensitized solar cells

Hedgehog-like hierarchical ZnO needle-clusters, three-dimensional (3-D) ZnO flowers and one-dimensional (1-D) ZnO needles have been synthesised via a facile hydrothermal method. These samples with different morphologies and microstructures were used to fabricate photoelectrodes for dye-sensitized solar cells (DSSCs). Out of the three samples, current–voltage (I–V) curve measurements show that DSSCs with hedgehog-like ZnO needle-clusters display the best photoelectrochemical performance which can be attributed to enhanced light harvesting and faster reaction kinetics resulting from the unique morphology. The UV-vis absorption and diffused reflectance spectra indicate that hedgehog-like ZnO needle-clusters show higher light harvesting abilities due to high UV absorption, stronger light scattering, as well as a high surface area. Electrochemical impedance spectroscopy (EIS), intensity-modulated photocurrent spectroscopy (IMPS), and intensity-modulated voltage spectroscopy (IMVS) further demonstrate that hedgehog-like ZnO needle-clusters provide superior electron transfer kinetics: fast electron transfer and long electron lifetimes with suppressed recombination. The ZnO needle-clusters obtained not only provide a 3-D matrix but also avoid extensive grain boundary formation. The discoveries from this work are important for the design of efficient photoanode materials with optimum structures for DSSCs.

[1]  Vijay Kumar,et al.  Doped zinc oxide window layers for dye sensitized solar cells , 2013 .

[2]  Jijiang Fu,et al.  A composite electrode of TiO2 nanotubes and nanoparticles synthesised by hydrothermal treatment for use in dye-sensitized solar cells , 2013 .

[3]  Vinod Kumar,et al.  Origin of the red emission in zinc oxide nanophosphors , 2013 .

[4]  P. Poddar,et al.  Growth of oriented single crystalline La-doped TiO2 nanorod arrays electrode and investigation of optoelectronic properties for enhanced photoelectrochemical activity , 2013 .

[5]  S. Bi,et al.  Mixed photoelectrode based on spherical TiO2 nanorod aggregates for dye-sensitized solar cells with high short-circuit photocurrent density , 2013 .

[6]  Liang-Yih Chen,et al.  Efficient electron transport in ZnO nanowire/nanoparticle dye-sensitized solar cells via continuous flow injection process , 2013 .

[7]  Qingbiao Li,et al.  A novel biomass coated Ag–TiO2 composite as a photoanode for enhanced photocurrent in dye-sensitized solar cells , 2013 .

[8]  Xiaolin Liu,et al.  Synthesis of long TiO2 nanotube arrays with a small diameter for efficient dye-sensitized solar cells , 2013 .

[9]  Man Jiang,et al.  Hierarchical ZnO architectures consisting of nanorods and nanosheets prepared via a solution route for photovoltaic enhancement in dye-sensitized solar cells , 2013 .

[10]  L. P. Purohit,et al.  Synthesis and characterization of aluminum-boron co-doped ZnO nanostructures , 2013 .

[11]  X. Tan,et al.  A simple and facile approach for synthesis of a free-standing TiO2 nanotube layer and its photovoltaic application , 2012 .

[12]  A. S. Nair,et al.  Electrical and optical properties of electrospun TiO2-graphene composite nanofibers and its application as DSSC photo-anodes , 2012 .

[13]  Kai Jiang,et al.  Hierarchical TiO2 microspheres: synthesis, structural control and their applications in dye-sensitized solar cells , 2012 .

[14]  R. Mane,et al.  Photoelectrochemistry of solution processed hematite nanoparticles, nanoparticle-chains and nanorods , 2012 .

[15]  B. Liu,et al.  Transfer of asymmetric free-standing TiO2 nanowire films for high efficiency flexible dye-sensitized solar cells , 2012 .

[16]  Tao Yu,et al.  Interfacial modification of photoelectrode in ZnO-based dye -sensitized solar cells and its efficiency improvement mechanism , 2012 .

[17]  Litao Sun,et al.  Hollow SnO2 microspheres for high-efficiency bilayered dye sensitized solar cell , 2012 .

[18]  A. S. Nair,et al.  TiO2 nanoparticles synthesized by the molten salt method as a dual functional material for dye-sensitized solar cells , 2012 .

[19]  William Wen,et al.  High-performance nanoporous TiO2/La2O3 hybrid photoanode for dye-sensitized solar cells. , 2012, ACS applied materials & interfaces.

[20]  Michael Grätzel,et al.  Porphyrin-Sensitized Solar Cells with Cobalt (II/III)–Based Redox Electrolyte Exceed 12 Percent Efficiency , 2011, Science.

[21]  D. Kuang,et al.  Tri-functional hierarchical TiO2 spheres consisting of anatase nanorods and nanoparticles for high efficiency dye-sensitized solar cells , 2011 .

[22]  Sang-Hoon Lim,et al.  Drip and evaporation method for dye-TiO2 nano junction formation in dye sensitized solar cells , 2011 .

[23]  Yantao Shi,et al.  ZnO hierarchical structures for efficient quasi-solid dye-sensitized solar cells. , 2011, Physical chemistry chemical physics : PCCP.

[24]  Peng Wang,et al.  Rutile TiO2 microspheres with exposed nano-acicular single crystals for dye-sensitized solar cells , 2011 .

[25]  Xueping Gao,et al.  Highly Pt-like electrocatalytic activity of transition metal nitrides for dye-sensitized solar cells , 2011 .

[26]  Litao Sun,et al.  Solution-derived ZnO nanostructures for photoanodes of dye-sensitized solar cells , 2011 .

[27]  G. R. Li,et al.  One-dimensional hierarchical titania for fast reaction kinetics of photoanode materials of dye-sensitized solar cells , 2010 .

[28]  Y. Tachibana,et al.  Dye-sensitized solar cells based on WO3. , 2010, Langmuir : the ACS journal of surfaces and colloids.

[29]  D. Kuang,et al.  Sonochemical preparation of hierarchical ZnO hollow spheres for efficient dye-sensitized solar cells. , 2010, Chemistry.

[30]  Chun-Te Wu,et al.  Three-dimensional zno nanodendrite/nanoparticle composite solar cells , 2010, 2010 35th IEEE Photovoltaic Specialists Conference.

[31]  Xueping Gao,et al.  Carbon nanotubes with titanium nitride as a low-cost counter-electrode material for dye-sensitized solar cells. , 2010, Angewandte Chemie.

[32]  W. Zhou,et al.  TiO2-B narrow nanobelt/TiO2 nanoparticle composite photoelectrode for dye-sensitized solar cells , 2009 .

[33]  Dong Young Kim,et al.  Charge Transport Characteristics of High Efficiency Dye-Sensitized Solar Cells Based on Electrospun TiO2 Nanorod Photoelectrodes , 2009 .

[34]  Song Jin,et al.  Potential applications of hierarchical branching nanowires in solar energy conversion , 2009 .

[35]  Rosaria Ciriminna,et al.  Nanochemistry aspects of titania in dye-sensitized solar cells , 2009 .

[36]  Claude Lévy-Clément,et al.  ZnO/CdSe nanowires and nanotubes: formation, properties and applications , 2009 .

[37]  Xueping Gao,et al.  Structure Transformation and Photoelectrochemical Properties of TiO2 Nanomaterials Calcined from Titanate Nanotubes , 2009 .

[38]  Sachin Kumar,et al.  High-Density Vertically Aligned ZnO Rods with a Multistage Terrace Structure and Their Improved Solar Cell Efficiency , 2008 .

[39]  Lianmao Peng,et al.  CdS quantum dots sensitized TiO2 nanotube-array photoelectrodes. , 2008, Journal of the American Chemical Society.

[40]  Taeghwan Hyeon,et al.  Nanorod‐Based Dye‐Sensitized Solar Cells with Improved Charge Collection Efficiency , 2008 .

[41]  Chen-Hao Ku,et al.  Chemical bath deposition of ZnO nanowire–nanoparticle composite electrodes for use in dye-sensitized solar cells , 2007 .

[42]  Laurence M. Peter,et al.  A Reappraisal of the Electron Diffusion Length in Solid-State Dye-Sensitized Solar Cells , 2007 .

[43]  K. Ho,et al.  A study on the electron transport properties of TiO2 electrodes in dye-sensitized solar cells , 2007 .

[44]  Joseph T Hupp,et al.  ZnO nanotube based dye-sensitized solar cells. , 2007, Nano letters.

[45]  Guo-Qiang Lo,et al.  Improved dye-sensitized solar cells with a ZnO-nanoflower photoanode , 2007 .

[46]  T. Berger,et al.  An Electrochemical Study on the Nature of Trap States in Nanocrystalline Rutile Thin Films , 2007 .

[47]  Chen-Hao Ku,et al.  Effects of dye adsorption on the electron transport properties in ZnO-nanowire dye-sensitized solar cells , 2007 .

[48]  Yukio Ogata,et al.  Determination of parameters of electron transport in dye-sensitized solar cells using electrochemical impedance spectroscopy. , 2006, The journal of physical chemistry. B.

[49]  Tsukasa Yoshida,et al.  Room‐Temperature Synthesis of Porous Nanoparticulate TiO2 Films for Flexible Dye‐Sensitized Solar Cells , 2006 .

[50]  Tsukasa Yoshida,et al.  Dye Sensitization of ZnO by Unsymmetrical Squaraine Dyes Suppressing Aggregation , 2006 .

[51]  K. West,et al.  An equivalent circuit approach to the modelling of the dynamics of dye sensitized solar cells , 2005 .

[52]  Emilio Palomares,et al.  Charge separation versus recombination in dye-sensitized nanocrystalline solar cells: the minimization of kinetic redundancy. , 2005, Journal of the American Chemical Society.

[53]  Michael Grätzel,et al.  Conversion of sunlight to electric power by nanocrystalline dye-sensitized solar cells , 2004 .

[54]  Takehito Mitate,et al.  Modeling of an equivalent circuit for dye-sensitized solar cells , 2004 .

[55]  Anders Hagfeldt,et al.  A 5% efficient photoelectrochemical solar cell based on nanostructured ZnO electrodes , 2002 .

[56]  P. Liska,et al.  Engineering of efficient panchromatic sensitizers for nanocrystalline TiO(2)-based solar cells. , 2001, Journal of the American Chemical Society.

[57]  Anders Hagfeldt,et al.  Studies of the adsorption process of Ru complexes in nanoporous ZnO electrodes , 2000 .

[58]  E. A. Ponomarev,et al.  Detection of inhomogeneous dye distribution in dye sensitised nanocrystalline solar cells by intensity modulated photocurrent spectroscopy (IMPS) , 1999 .

[59]  L. Peter,et al.  Frequency-Resolved Optical Detection of Photoinjected Electrons in Dye-Sensitized Nanocrystalline Photovoltaic Cells , 1999 .

[60]  Hong-Yan Chen,et al.  High-performance dye-sensitized solar cells based on hierarchical yolk–shell anatase TiO2beads , 2012 .

[61]  Kai Zhu,et al.  Enhanced charge-collection efficiencies and light scattering in dye-sensitized solar cells using oriented TiO2 nanotubes arrays. , 2007, Nano letters.

[62]  Tomas Edvinsson,et al.  Comparison of Dye-Sensitized ZnO and TiO2 Solar Cells: Studies of Charge Transport and Carrier Lifetime , 2007 .

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