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1.
Johann Boucl Sabina Chyla Milo S. P. Shaffer James R. Durrant Donal D. C. Bradley Jenny Nelson 《Advanced functional materials》2008,18(4):622-633
Hybrid bulk heterojunction solar cells based on nanocrystalline TiO2 (nc‐TiO2) nanorods capped with trioctylphosphine oxide (TOPO) and regioregular poly(3‐hexylthiophene) (P3HT) are processed from solution and characterized in order to relate the device function (optical absorption, charge separation, and transport and photovoltaic properties) to active‐layer properties and device parameters. Annealing the blend films is found to greatly improve the polymer–metal oxide interaction at the nc‐TiO2/P3HT interface, resulting in a six‐fold increase of the charge separation yield and improved photovoltaic device performance under simulated solar illumination. In addition, the influence of the organic ligand at the nc‐TiO2 particle surface is found to be crucial for charge separation. Ligand‐exchange procedures applied on the TOPO‐capped nc‐TiO2 nanorods with an amphiphilic ruthenium‐based dye are found to further improve the charge‐separation yield at the polymer–nanocrystal interface. However, the poor photocurrents generated in the hybrid blend devices, before and after ligand exchange, suggest that transport within or between nanoparticles limits performance. By comparison with other donor–acceptor bulk heterojunction systems, we conclude that charge transport in the nc‐TiO2:P3HT blend films is limited by the presence of an intrinsic trap distribution mainly associated with the nc‐TiO2 particles. 相似文献
2.
Yen‐Fong Chan Cheng‐Chien Wang Bing‐Hung Chen Chuh‐Yung Chen 《Progress in Photovoltaics: Research and Applications》2013,21(1):47-57
A series of anatase TiO2‐based nanocomposite incorporated with plasma‐modified multi‐walled carbon nanotubes (MWNTs) was prepared by physical blending and shows its capability for efficient electron transport when used as photoanode in dye‐sensitized solar cells (DSSCs). These MWNTs characterized with good dispersal performance were obtained by functionalization technique via in situ plasma treatment and subsequent grafting with maleic anhydride (MA) onto the external walls reported previously. Compared with the conventional DSSCs, the TiO2 film with 1D carbon nanotubes possesses more outstanding ability to transport electrons injected from the excited dye within the device under illumination. As a result, at an optimum addition of 0.3 wt% MWNTs‐MA in TiO2 matrix, the photocurrent–voltage (J–V) characteristics showed a significant increase in the short‐circuit photocurrent (Jsc) of 50%, leading to an increase in overall solar conversion efficiency by a factor of 1.5. Electrochemical impedance spectroscopy analyses reveal that the MWNTs‐MA/TiO2 incur smaller resistances at the photoanode in assembled DSSCs when compared with those in the anatase titania DSSCs. These features suggest that the conducting properties of the MWNTs‐MA within the anodes are crucial for achieving a higher transport rate for photo‐induced electrons in TiO2 layer by exhibiting lower resistance in the porous network and hence retard charge recombination that could result in poor conversion efficiency. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
3.
High Efficiency Solid‐State Dye‐Sensitized Solar Cells Assembled with Hierarchical Anatase Pine Tree‐like TiO2 Nanotubes
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Dong Kyu Roh Won Seok Chi Harim Jeon Sang Jin Kim Jong Hak Kim 《Advanced functional materials》2014,24(3):379-386
A facile and effective method to prepare hierarchical pine tree‐like TiO2 nanotube (PTT) arrays with an anatase phase directly grown on a transparent conducting oxide substrate via a one‐step hydrothermal reaction. The PTT arrays consist of a vertically oriented long nanotube (NT) stem and a large number of short nanorod (NR) branches. Various PTT morphologies are obtained by adjusting the water/diethylene glycol ratio. The diameter of the NTs and the size of the NR branches decreases from 300 to100 nm and from 430 to 230 nm, respectively, with increasing water content. The length of the PTT arrays could be increased up to 19 μm to significantly improve the charge transport and specific surface area. The solid‐state dye‐sensitized solar cells (ssDSSC) assembled with the 19 μm long PTT arrays exhibit an outstanding energy‐conversion efficiency of 8.0% at 100 mW/cm2, which is two‐fold higher than that of commercially available paste (4.0%) and one of the highest values obtained for N719 dye‐based ssDSSCs. The high performance is attributed to the larger surface area, improved electron transport, and reduced electrolyte/electrode interfacial resistance, resulting from the one‐dimensional, well‐aligned structure with a high porosity and large pores. 相似文献
4.
Di Zhang Wallace C. H. Choy Fengxian Xie Wei E. I. Sha Xinchen Li Baofu Ding Kai Zhang Fei Huang Yong Cao 《Advanced functional materials》2013,23(34):4255-4261
Optical effects of the plasmonic structures and the materials effects of the metal nanomaterials have recently been individually studied for enhancing performance of organic solar cells (OSCs). Here, the effects of plasmonically induced carrier generation and enhanced carrier extraction of the carrier transport layer (i.e., plasmonic‐electrical effects) in OSCs are investigated. Enhanced charge extraction in TiO2 as a highly efficient electron transport layer by the incorporation of metal nanoparticles (NPs) is proposed and demonstrated. Efficient device performance is demonstrated by using Au NPs incorporated TiO2 at a plasmonic wavelength (560–600 nm), which is far longer than the originally necessary UV light. By optimizing the concentration ratio of the Au NPs in the NP‐TiO2 composite, the performances of OSCs with various polymer active layers are enhanced and efficiency of 8.74% is reached. An integrated optical and electrical model, which takes into account plasmonic‐induced hot carrier tunneling probability and extraction barrier between TiO2 and the active layer, is introduced. The enhanced charge extraction under plasmonic illumination is attributed to the strong charge injection of plasmonically excited electrons from NPs into TiO2. The mechanism favors trap filling in TiO2, which can lower the effective energy barrier and facilitate carrier transport in OSCs. 相似文献
5.
One‐dimensional (1D) nanostructures of TiO2 are grown directly on transparent, conductive glass substrate using hydrothermal/solvothermal methods. When employed as a photoanode in photoelectrochemical cells, the vertically aligned TiO2 nanorod array exhibits slower charge recombination at electrolyte interface as compared to mesoscopic TiO2 particulate film. Electrochemical deposition of CdSe onto TiO2 nanorod array is carried out to extend absorption into visible light region. The role of CdSe‐sensitized, 1D rutile TiO2 architecture in the solar cell design is discussed. 相似文献
6.
Solar Water Splitting by TiO2/CdS/Co–Pi Nanowire Array Photoanode Enhanced with Co–Pi as Hole Transfer Relay and CdS as Light Absorber
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Guanjie Ai Hongxing Li Shaopei Liu Rong Mo Jianxin Zhong 《Advanced functional materials》2015,25(35):5706-5713
The cobalt phosphate water oxidation catalyst (Co–Pi WOC) stabilized, CdS sensitized TiO2 nanowire arrays for nonsacrificial solar water splitting are reported. In this TiO2/CdS/Co–Pi photoanode, the Co–Pi WOC acts as hole transfer relay to accelerate the surface water oxidation reaction, CdS serves as light absorber for wider solar spectra harvesting, and TiO2 matrix provides direct pathway for electron transport. This triple TiO2/CdS/Co–Pi hybrid photoanode exhibits much enhanced photocurrent density and negatively shifts in onset potential, resulting in 1.5 and 3.4 times improved photoconversion efficiency compared to the TiO2/CdS and TiO2 photoanode, respectively. More importantly, the TiO2/CdS/Co–Pi shows significantly improved photoelectrochemical stability compared to the TiO2/CdS electrode, with ≈72% of the initial photocurrent retained after 2 h irradiation. The reason for the promoted performance is discussed in detail based on electrochemical measurements. This work provides a new paradigm for designing 1D nanoframework/light absorber/WOC photoanode to simultaneously enhance light absorption, charge separation, and transport and surface water oxidation reaction for efficient and stable solar fuel production. 相似文献
7.
This paper reports the synthesis of nanosized TiO2 single crystals with different percentages of exposed (001) facets in the presence of HF solution. Various characterizations are conducted to understand the correlation between particle morphology, exposed (001) facets and photo‐conversion efficiency of the nanosized anatase TiO2 single crystals. An enhancement in dye‐sensitized solar cells (DSSCs) overall conversion efficiency is observed for the photoanode consisting of nanosized TiO2 single crystals with higher percentage of exposed (001) facets, increasing from 7.47%, 8.14% to 8.49% for the TiO2 single crystals with ca. 10%, 38%, and 80% percentage of exposed (001) facets. Experimentally confirmed by dark current potential and open‐circuit voltage decay scans, such highly exposed (001) facets are not only favorable for more dye adsorption but also effectively retard the charge recombination process in DSSCs. 相似文献
8.
Photovoltaic performance of dye sensitized solar cell (DSSC) with absorber layer of TiO2 nanotube (NT)/TiO2 nanoparticles (NPs)/ZnO NPs was investigated. Fabricated DSSC exhibits enhanced open circuit voltage, current density and power conversion efficiency compared with DSSC having absorber layer of TiO2 NT/ TiO2 NPs and TiO2 NT/ZnO NPs. To further explore the dynamics of charge transport and recombination processes, electrochemical impedance analysis, intensity modulated photovoltage spectroscopy and photocurrent spectroscopy were carried out on the fabricated DSSCs. It was found that an optimal combination of TiO2/ZnO NPs on top of TiO2 NTs reduces the electron recombination and improves transport pathways, resulting in an efficient charge collection of 99%. 相似文献
9.
Young Gon Seo Kyoungja Woo Junkyung Kim Hyunjung Lee Wonmok Lee 《Advanced functional materials》2011,21(16):3094-3103
A rapid fabrication method of highly reflective TiO2 inverse opal (IO) film exhibiting controllable thickness, high TiO2 content, and excellent interfacial contact with glass substrate is presented. By inducing accelerated solvent evaporation during the colloidal self‐assembly process, a composite film of polystyrene (PS)/TiO2 has been directly fabricated on a fluorine doped tin oxide (FTO) glass substrate, which exhibits the highly ordered opaline structure of PS embedded into the TiO2 matrix. This hybrid fabrication path leads to the formation of layers with the preferred {111} face‐centered cubic (FCC) orientation parallel to the substrate and to produce a 1 cm2‐wide well‐ordered composite colloidal crystal film in less than 30 min. The film showed highly ordered FCC structure, particularly at the upper region, due to the induced solvent evaporation and exhibited a reliable light modulation at a reflectance mode. Regardless of the size of sacrificial PS microspheres, TiO2 IO films of controllable thickness were successfully formed by varying the moving speed of the fabrication cell. The binary aqueous dispersion of tailor‐made anatase TiO2 nanoparticles and monodisperse PS microspheres showed a high degree of dispersion stability under basic conditions. Hydrothermal treatment of the TiO2 dispersion favored the crystallinity of the coated film and provided small volume contraction after thermal calcinations. The high degree of dispersion stability enabled to increase TiO2 content in a binary mixture, which is more favorable toward the robust and large‐area IO film. The calcined films exhibited excellent mechanical robustness and intimate interfacial contact with the glass substrate. which in turn resulted in higher TiO2 content near the glass substrate. The TiO2 IO film was tested as a dye‐sensitized solar cell (DSSC) photoelectrode, and a single cell showed a relatively high photon‐to‐current conversion efficiency of 4.2%. The high TiO2 content of IO film and its good adhesion to the FTO subratrate remarkably improved in the performance of the solar cell compared to the previous investigations where post‐infiltration of TiO2 had been employed. 相似文献
10.
Jin-Su Jeong Byung-Hak Choe Jung-Ho Lee Jae-Joon Lee Won-Youl Choi 《Journal of Electronic Materials》2014,43(2):375-380
In dye-sensitized solar cells, highly ordered TiO2 nanotube arrays as a photoelectrode have higher charge collection efficiencies than a nanoparticle-based structure due to their faster charge percolation and slower recombination of electrons. Highly ordered TiO2 nanotube arrays were grown by anodic oxidation of 0.5-mm-thick titanium foil. To increase the conversion efficiency of dye-sensitized solar cells with TiO2 nanotube arrays, the surface of the TiO2 nanotube arrays was modified by zinc oxide thin films. The ZnO thin film was formed by atomic layer deposition. The thin film was conformal on the inner and outer walls of TiO2 nanotube arrays. ZnO thin film improved the short circuit current (J sc) and open circuit voltage (V oc) due to increasing specific surface area from particulates of ZnO thin film and increasing the surface charge induced from the isoelectric point. The power conversion efficiency of dye-sensitized solar cells with ZnO thin film on 4.5-μm-thick TiO2 nanotube arrays was 1.43%. Microstructure and phase were observed by scanning electron microscopy, x-ray diffractometry, and transmission electron microscopy. 相似文献
11.
A series of perovskite-based solar cells were fabricated wherein a compact layer (CL) of TiO2 of varying thickness (0–390 nm) was introduced by spray pyrolysis deposition between fluorine-doped tin oxide (FTO) electrode and TiO2 nanoparticle layer in perovskite-based solar cells. Investigations of the CL thickness-dependent current density–voltage (J–V) characteristics, dark current, and open circuit voltage (Voc) decays showed a similar trend for thickness dependence. A CL thickness of 90 nm afforded the perovskite-based solar cell with the maximum power conversion efficiency (η, 3.17%). Furthermore, two additional devices, perovskite-based solar cell omitting hole transporting materials layer and cell without the TiO2 nanoparticles, were designed and fabricated to study the influence of the CL thickness on different electron transport paths in perovskite-based solar cells. Solar cells devoid of TiO2 nanoparticles, but with perovskite and organic hole-transport materials (HTMs), exhibited sustained improvement in photovoltaic performances with increase in the thickness of CL, which is in contrast to the behavior of classical perovskite-based solar cell and common solid state solar cell which showed optimal photovoltaic performances when the thickness of CL is 90 nm. These observations suggested that TiO2 nanoparticles play a significant role in electron transport in perovskite-based solar cells. 相似文献
12.
Sawanta S. Mali Pravin S. Shinde Chirayath A. Betty Popatrao N. Bhosale Won J. Lee Pramod S. Patil 《Progress in Photovoltaics: Research and Applications》2014,22(5):525-539
Multistep hydrothermal (MSH) process is employed for growth of TiO2 nanocorals onto the conducting fluorine‐doped tin oxide‐coated glass substrates. The surface morphological features and physical properties of TiO2 films were investigated by field emission scanning electron microscopy, high resolution transmission electron microscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, Fourier transform Raman spectroscopy, room temperature photoluminescence spectroscopy and X‐ray photoelectron spectroscopy. The surface morphology revealed the formation of TiO2 corals having nanosized (30–40 nm) polyps. The photoelectrochemical properties of the TiO2 nanocoral electrodes were investigated in 0.1 M NaOH electrolyte under ultraviolet illumination. The results presented in this study highlight two major findings: (i) tuning the photoelectrochemical response and photoconversion efficiency via controlled thickness of TiO2 nanocorals by MSH route and (ii) the substantial increase in short‐circuit photocurrent (Jsc) because of the improved charge transport through TiO2 nanocorals prepared via MSH process. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
13.
Photoelectrochemically Active and Environmentally Stable CsPbBr3/TiO2 Core/Shell Nanocrystals
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Zhi‐Jun Li Elan Hofman Jian Li Andrew Hunter Davis Chen‐Ho Tung Li‐Zhu Wu Weiwei Zheng 《Advanced functional materials》2018,28(1)
Inherent poor stability of perovskite nanocrystals (NCs) is the main impediment preventing broad applications of the materials. Here, TiO2 shell coated CsPbBr3 core/shell NCs are synthesized through the encapsulation of colloidal CsPbBr3 NCs with titanium precursor, followed by calcination at 300 °C. The nearly monodispersed CsPbBr3/TiO2 core/shell NCs show excellent water stability for at least three months with the size, structure, morphology, and optical properties remaining identical, which represent the most water‐stable inorganic shell passivated perovskite NCs reported to date. In addition, TiO2 shell coating can effectively suppress anion exchange and photodegradation, therefore dramatically improving the chemical stability and photostability of the core CsPbBr3 NCs. More importantly, photoluminescence and (photo)electrochemical characterizations exhibit increased charge separation efficiency due to the electrical conductivity of the TiO2 shell, hence leading to an improved photoelectric activity in water. This study opens new possibilities for optoelectronic and photocatalytic applications of perovskites‐based NCs in aqueous phase. 相似文献
14.
Trifunctional TiO2 Nanoparticles with Exposed {001} Facets as Additives in Cobalt‐Based Porphyrin‐Sensitized Solar Cells
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Peng Zhai Tsung‐Yu Hsieh Chen‐Yu Yeh Kamani Sudhir K Reddy Chi‐Chang Hu Jhih‐Hao Su Tzu‐Chien Wei Shien‐Ping Feng 《Advanced functional materials》2015,25(38):6093-6100
In this study, highly mesoporous TiO2 composite photoanodes composed of functional {001}‐faceted TiO2 nanoparticles (NPs) and commercially available 20 nm TiO2 NPs are employed in efficient porphyrin‐sensitized solar cells together with cobalt polypyridyl‐based mediators. Large TiO2 NPs (approximately 50 nm) with exposed {001} facets are prepared using a fast microwave‐assisted hydrothermal (FMAH) method. These unique composite photoanodes favorably mitigate the aggregation of porphyrin on the surface of TiO2 NPs and strongly facilitate the mass transport of cobalt‐polypyridyl‐based electrolytes in the mesoporous structure. Linear sweep voltammetry reveals that the transportation of Co(polypyridyl) redox is a diffusion‐controlled process, which is highly dependent on the porosity of TiO2 films. Electrochemical impedance spectroscopy confirms that the FMAH TiO2 NPs effectively suppress the interfacial charge recombination toward [Co(bpy)3]3+ because of their oxidative {001} facets. In an optimal condition of 40 wt% addition of FMAH TiO2 NPs in the final formula, the power conversion efficiency of the dye‐sensitized cells improves from 8.28% to 9.53% under AM1.5 (1 sun) conditions. 相似文献
15.
Seung‐Taek Myung Naohiro Takahashi Shinichi Komaba Chong Seung Yoon Yang‐Kook Sun Khalil Amine Hitoshi Yashiro 《Advanced functional materials》2011,21(17):3231-3241
Titania nanorods and nanowires are synthesized via a hydrothermal reaction of amorphous TiO2 in alkaline NaOH, followed by ion exchange in HCl aqueous solution, and dehydration at 400 °C. Although the hydrothermal treatment produces three different particle morphologies depending on the reaction time (nanosheets, nanorods, and nanowires), the products exhibit the same crystal structure. Ion exchange of Na2Ti3O7 in HCl aqueous solution brings about a phase change to H2Ti3O7, but there is no change in the particle morphology. Dehydration of the nanostructured H2Ti3O7 leads to two types of crystal structure—anatase TiO2 for the nanorods, and TiO2–B for the nanowires—although no significant difference is found in the morphology of the products even after dehydration. The nanorods are 40–50 nm in length and 10 nm in diameter, whereas the nanowires are several micrometers in length and tens to hundreds of nanometers in thickness. In‐situ X‐ray diffraction revealed the formation of anatase TiO2 from the TiO2–B above 450 °C. This finding implies that the phase transformation occurs rather slowly for the TiO2–B nanowires due to the larger particle size and higher crystallinity of H2Ti3O7. Tests with Li‐metal half cells indicated that the anatase TiO2 nanorods are more favorable for the storage and release of Li ions because of their greater surface area than the TiO2–B nanowires. 相似文献
16.
Pablo Docampo Stefan Guldin Morgan Stefik Priti Tiwana M. Christopher Orilall Sven Hüttner Hiroaki Sai Ulrich Wiesner Ulrich Steiner Henry J. Snaith 《Advanced functional materials》2010,20(11):1787-1796
Hybrid dye‐sensitized solar cells are typically composed of mesoporous titania (TiO2), light‐harvesting dyes, and organic molecular hole‐transporters. Correctly matching the electronic properties of the materials is critical to ensure efficient device operation. In this study, TiO2 is synthesized in a well‐defined morphological confinement that arises from the self‐assembly of a diblock copolymer—poly(isoprene‐b‐ethylene oxide) (PI‐b‐PEO). The crystallization environment, tuned by the inorganic (TiO2 mass) to organic (polymer) ratio, is shown to be a decisive factor in determining the distribution of sub‐bandgap electronic states and the associated electronic function in solid‐state dye‐sensitized solar cells. Interestingly, the tuning of the sub‐bandgap states does not appear to strongly influence the charge transport and recombination in the devices. However, increasing the depth and breadth of the density of sub‐bandgap states correlates well with an increase in photocurrent generation, suggesting that a high density of these sub‐bandgap states is critical for efficient photo‐induced electron transfer and charge separation. 相似文献
17.
The search for low‐cost thin‐film solar cells, to replace silicon multi‐crystalline cells in due course, calls for new combinations of materials and new cell configurations. Here we report on a new approach, based on semiconductor nanocomposites, towards what we refer to as the three‐dimensional (3D) solar‐cell concept. Atomic layer chemical vapor deposition is employed for infiltration of CuInS2 inside the pores of nanostructured TiO2. In this way it is possible to obtain a nanometer‐scale interpenetrating network between n‐type TiO2 and p‐type CuInS2. X‐ray diffraction, Raman spectroscopy, photoluminescence spectroscopy, scanning electron microscopy, transmission electron microscopy, and current–voltage measurements are used to characterize the nanostructured devices. The 3D solar cells obtained show photovoltaic activity with a maximum monochromatic incident photon‐to‐current conversion efficiency of 80 % and have an energy‐conversion efficiency of 4 %. 相似文献
18.
Multiwalled carbon nanotube/TiO2 multilayer nanocomposite was successfully deposited on the fluorine-doped tin oxide (FTO) glass via layer-by-layer assembly technique to modify interfacial contact between the FTO surface and nanocrystalline TiO2 layer as well as carbon nanotube/TiO2 contacts in photoanode of dye sensitized solar cell. Using this approach, binder-free interfacial thin film was developed with nonagglomerated, well-dispersed MWCNTs on FTO and into TiO2 matrix and with maximum covering of TiO2 nanoparticles on MWCNTs. Introduction of MWCNTs/TiO2 interfacial layer into the TiO2 photoanode increased short circuit current density (Jsc) from 11.90 to 17.25 mA/cm2 and open circuit voltage (Voc) from 730 mV to 755 mV, whereas there was no notable change in the fill factor (FF). Consequently, power conversion efficiency (η) was enhanced from 5.32% to 7.53%, yielding a 41.5% enhancement. The results suggest that our simple strategy can integrate reduction of back electron reaction at FTO/TiO2 interface with the effective charge transport ability of carbon nanotubes and possessing high surface area for efficient dye loading. 相似文献
19.
Novel Cu2O/Pt/TiO2 three-layered nanocomposite films were prepared by deposition on glass substrates using the magnetron sputtering method. Their structure, surface morphology as well as optical and photocatalytic properties were examined by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, UV–visible spectroscopy, and photoluminescence spectroscopy. As a comparison, Cu2O/TiO2 double-layer films were also investigated. The results show that Cu2O/TiO2 double-layer films have relatively smooth surfaces with agglomerated Cu2O particle, whereas the surface layer of the Cu2O/Pt/TiO2 three-layered nanocomposite films was composed of fine nano-sized columnar Cu2O and they had a rough surface morphology due to the insertion of the Pt layer. The photocatalytic activity of the three-layered films is significantly higher than that of the Cu2O/TiO2 double-layered composite films. Such enhancement is closely related to the presence of the Pt layer and the rough surface, which was composed of fine nano-sized Cu2O columns; this increases the utilization of visible light as well as promotes the transfer of interfacial charge and the separation of photogenerated electron–holes. 相似文献
20.
Lu‐Yin Lin Chuan‐Pei Lee Keng‐Wei Tsai Min‐Hsin Yeh Chia‐Yuan Chen R. Vittal Chun‐Guey Wu Kuo‐Chuan Ho 《Progress in Photovoltaics: Research and Applications》2012,20(2):181-190
An energy‐economical dye‐sensitized solar cell (DSSC) with highly flexible Ti/TiO2 photoanode was developed through a low‐temperature process, using a binder‐free TiO2 paste. Ti foils, coated with the binder‐free TiO2 films were annealed at various temperature. Scanning electron microscopic (SEM) images of the films show uniform, mesoporous and crack‐free surface morphologies as well as interpenetrated TiO2 network. DSSCs with binder‐free TiO2 films annealed at 450, 350, 250 and 120°C show solar‐to‐electricity conversion efficiencies (η) of 4.33, 4.34, 3.72 and 3.40%, respectively, which are comparable to the efficiency of 4.56% obtained by using a paste with binder and annealing it at 450°C; this observation demonstrates the benefits of a binder‐free TiO2 paste for the fabrication of energy‐fugal DSSCs. On the other hand, when organic binder was used in the TiO2 paste for film preparation, a drastic deterioration in the cell performance with decreasing annealing temperature is noticed. Laser‐induced photo‐voltage transient technique is used to estimate the electron lifetime in various Ti/TiO2 films. Electrochemical impedance spectroscopic (EIS) analysis shows that the lower the annealing temperature of the TiO2 coated Ti foil, the larger the charge transfer resistance at the TiO2/dye/electrolyte interface (Rct2). Copyright © 2011 John Wiley & Sons, Ltd. 相似文献