The ZnO-modified TiO2 electrode was prepared by adding Zn（CH3COO）2·2H2O to the TiO2 colloid during the sol-gel production process, and was used in dye-sensitized solar cells （DSCs）. The open circuit voltage ...The ZnO-modified TiO2 electrode was prepared by adding Zn（CH3COO）2·2H2O to the TiO2 colloid during the sol-gel production process, and was used in dye-sensitized solar cells （DSCs）. The open circuit voltage （Voc） and fill factor （if） of the cells were improved sig- nificantly. The performances of the ZnO-modified TiO2 electrode such as dark current, transient photocurrent, impedance, absorption spectra, and fiat band potential （Vfb） were investigated. It is found that the interface charge recombination impedance increases and Vfb shifts about 200 mV toward the cathodic potential. The effect mechanism of ZnO modification on the performance of DSCs may be that ZnO occupies the surface states of the TiO2 film.展开更多
Photocatalytic oxidation desulfurization has become a research hotspot in recent years because of mild reaction conditions, less energy consumption and high selectivity. In this paper, TiO2 was loaded onto SBA-15 mole...Photocatalytic oxidation desulfurization has become a research hotspot in recent years because of mild reaction conditions, less energy consumption and high selectivity. In this paper, TiO2 was loaded onto SBA-15 molecular sieves and sensitized with organic dyes(2, 9-dichloroquinacridone, DCQ) to extend its spectral response range from ultraviolet light to visible light. The catalyst DCQ-X%TiO2@SBA-15 was characterized by BET measurements, X-ray diffraction, Fourier transform infrared spectroscopy and Ultraviolet-visible diffuse reflection spectra, and then it was applied for photocatalytic oxidation desulfurization of gasoline. The effects of different catalytic systems, TiO2 concentration, catalyst dosage, and different model sulfur compounds on catalytic desulfurization performance were investigated. Experimental results show that DCQ-TiO2@SBA-15 has a better performance than the unsensitized TiO2@SBA-15, and the desulfurization rate can reach up to 96.1% in a reaction time of 90 min.展开更多
Titanium tetrachloride (TiCl4) treatment was employed to TiO2 coating deposited on fluoride-doped tin oxide (FTO) conducting glass and indium oxide doped tin oxide (ITO) conducting glass, respectively. The nano-crysta...Titanium tetrachloride (TiCl4) treatment was employed to TiO2 coating deposited on fluoride-doped tin oxide (FTO) conducting glass and indium oxide doped tin oxide (ITO) conducting glass, respectively. The nano-crystalline TiO2 coating was deposited using a composite powder composed of polyethylene glycol (PEG) and 25 nm TiO2 particles by vacuum cold spraying (VCS) process. A commercial N-719 dye was used to adsorb on the surface of TiO2 coating to prepare TiO2 electrode, which was applied to assemble dye-sensitized solar cell (DSC). The cell performance was measured under simulated solar light at an intensity of 100 mW·cm-2. Results show that with an FTO substrate the DSC composed of a VCS TiO2 electrode untreated by TiCl4 gives a short-circuit current density of 13.1 mA·cm-2 and an open circuit voltage of 0.60 V corresponding to an overall conversion efficiency of 4.4%. It is found that after TiCl4 treatment to the VCS TiO2 electrode with an FTO substrate, the short circuit current density of the cell increases by 31%, the open-circuit voltage increases by 60 mV and a higher conversion yield of 6.5% was obtained. However, when an ITO substrate is used to deposit TiO2 coating by VCS, after TiCl4 treatment, the conversion efficiency of the assembled cell reduces slightly due to corrosion of the conducting layer on the ITO glass by TiCl4.展开更多
Single-crystalline anatase TiO2nanorods have been prepared by solvothermal method using tetrabutylammonium hydroxide（TBAH） as a morphology controlling agent.The obtained TiO2nanorods are dominated by a large percent...Single-crystalline anatase TiO2nanorods have been prepared by solvothermal method using tetrabutylammonium hydroxide（TBAH） as a morphology controlling agent.The obtained TiO2nanorods are dominated by a large percentage of {010} facets.The power conversion efficiency of dye-sensitized solar cell（DSSC） based on anatase TiO2nanorods（8.66%） exhibits a significant improvement（35%） compared to that of P25 TiO2（5.66%）.The high performance of the anatase TiO2nanorods solar cell is ascribed to their large percent of exposed {010} facets as well as balancing their surface areas and sizes.展开更多
Modified with gadolinium-containing layer, nanoporous titania electrode and its application in dye-sensitized solar cells were reported. The electrode prepared was characterized with UV-Vis and X-ray diffraction （XRD...Modified with gadolinium-containing layer, nanoporous titania electrode and its application in dye-sensitized solar cells were reported. The electrode prepared was characterized with UV-Vis and X-ray diffraction （XRD） techniques. The amount of gadolinium was measured with inductively coupled plasma-optical emission spectrometry （ICP-OES） experiments. The modified electrode showed reduced N3 dye adsorption ability, but increased light conversion efficiency in comparison with the non-modified electrode. The overall conversion efficiencies, determined under 400 W/m2 irradiation with tungsten-halogen lamp at room temperature, were 0.55% for non-modified and 0.74% for modified electrodes.展开更多
Three different types of TiO2 nano powders were synthesized by a solution combustion synthesis （SCS） method using three different fuels and for comparison, another type of Ti2 nano powder was synthesized by calcinat...Three different types of TiO2 nano powders were synthesized by a solution combustion synthesis （SCS） method using three different fuels and for comparison, another type of Ti2 nano powder was synthesized by calcination of titanyl hydroxide. These TiO2 nano powders were used to fabricate photoelectrodes for the dye-sensitized solar cell （DSSC） and their performance was compared to that of the DSSC fabricated with Degussa P25 TiO2. The results showed that the SCS TiO2 could work well as photoelectrode for DSSC. The SCS TiO2 contained impurities of C and/or S, thus exhibiting visible light absorption and reduced band gap. The open circuit voltage and the fill factor both varied little among the various TiO2 and thus both had little effect on the photoelectrical conversion efficiency （η）. However, the variation of r/was seen to be in quite a good agreement with that of the short circuit current （Isc）, suggesting that r/was dominated by Isc. lsc was found to be enhanced by light scattering effect due to the presence of large particles but reduced by high impurity content due to an increase in electron transfer resistance. In addition, the specific surface area of the powders was found to be an important factor affecting the Isc and thus the η.展开更多
In this study,TiO2@MgO core-shell film was obtained by using a simple chemical bath deposition method to coat a thin MgO film around TiO2 nanoparticles. The core-shell configuration was characterized by X-ray diffract...In this study,TiO2@MgO core-shell film was obtained by using a simple chemical bath deposition method to coat a thin MgO film around TiO2 nanoparticles. The core-shell configuration was characterized by X-ray diffractometer (XRD),scanning elec-tron microscopy (SEM),energy dispersive X-ray spectroscopy (EDX),and high-resolution transmission electron microscopy (HRTEM). Lattice fringes were observed for the TiO2 particles,and the MgO shell showed an amorphous structure,revealing a clear distinction between the core and shell materials. Applying the core-shell film as photoanode to the dye-sensitized solar cells (DSSCs),it shows a superior performance compared to the pure TiO2 electrode. Under the illumination of simulated sunlight (75 mW-cm-2),the short circuit photocurrent (Jsc),the open circuit photovoltage (Voc),and the fill factor (fF) are 8.80 mA-cm-2,646 mV,and 0.69,respectively,and the conversion efficiency (η) in-creased by 21.8% (from 4.32% to 5.26%) when dipping for opti-mum condition.展开更多
In this work, a three-layer TiO2 composite film consisting of flower-like TiO2 （Flo-TiO2） as overlayer, TiOa nanotube arrays as interlayer and TiO2 nanoparticle （P25） as underlayer was fabricated as the photoelect...In this work, a three-layer TiO2 composite film consisting of flower-like TiO2 （Flo-TiO2） as overlayer, TiOa nanotube arrays as interlayer and TiO2 nanoparticle （P25） as underlayer was fabricated as the photoelectrode of dyesensitized solar cells （DSSCs）. Due to the introduction of Flo-TiO2, the three-layer composite film has strong lightscattering ability. Then, we have investigated and compared the photoelectric conversion properties of DSSCs based on three-layer structure （P25/TNT arrays/Flo-TiO2） photoelectrode and double-layer film （P25/TNT arrays） photoelectrode. It is found that DSSCs based on three-layer structure exhibit a high power conversion efficiency of 6.48% compared with the DSSCs composed of double-layer film （5.11%）.展开更多
TiO2 is a wide band gap semiconductor with important applications in photovoltaic cells. Vertically aligned Tit2 nanorod arrays （NRs） are grown on the fluorine-doped tin oxide （FTO） substrates by a multicycle hydr...TiO2 is a wide band gap semiconductor with important applications in photovoltaic cells. Vertically aligned Tit2 nanorod arrays （NRs） are grown on the fluorine-doped tin oxide （FTO） substrates by a multicycle hydrothermal synthesis process. The samples are characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, high-resolution transmission electron microscopy （HRTEM）, and selected-area electron diffraction （SAED）. It is found that dye-sensitized solar cells （DSSCs） assembled by the as-prepared Tit2 single-crystal NRs exhibit different trends under the condition of different nucleation and growth concentrations. Optimum cell performance is obtained with high nucleation concentration and low growth cycle concentration. The efficiency enhancement is mainly attributed to the improved specific surface area of the nanorod.展开更多
A dye-sensitized TiO2 solid solar cell, which contains poly(4-vinylphenyloxy-methyltriphenylamine) in hole transport layer (HTL) doped with LiSCN and methyl-hexyl-imidazolium iodide (MHIml), was prepared. The solar ce...A dye-sensitized TiO2 solid solar cell, which contains poly(4-vinylphenyloxy-methyltriphenylamine) in hole transport layer (HTL) doped with LiSCN and methyl-hexyl-imidazolium iodide (MHIml), was prepared. The solar cell shows that the conversion efficiency is 0.59%, Jsc is 3.03mA/cm2, and V^ is 0.53V at 1 sun light intensity.展开更多
The performance of dye-sensitized solar cells（DSSCs） consisting of anatase TiO_2 nanoparticles that were synthesized via a hydrothermal method was studied.The synthesized TiO_2 nanoparticles were characterized by X-...The performance of dye-sensitized solar cells（DSSCs） consisting of anatase TiO_2 nanoparticles that were synthesized via a hydrothermal method was studied.The synthesized TiO_2 nanoparticles were characterized by X-ray diffraction（XRD）,nitrogen sorption analysis,scanning electron microscopy（SEM）,high resolution transmission electron microscopy（HRTEM）,and UV-vis spectroscopy.Then the J-Vcurve,electrochemical impedance spectroscopy（EIS）,and open-circuit voltage decay（OCVD） measurement were applied to evaluate the photovoltaic performance of DSSCs.Compared with the commercial TiO_2nanoparticles（P25）,the synthesized-TiO_2 nanoparticles showed better performance.By adding diethylene glycol（DEG） before the hydrothermal process,the synthesized TiO_2 nanoparticles（hereafter referred to as TiO_2-DEG particles） shows narrower size distribution,larger specific surface area,higher crystallinity,and less surface defects than TiO_2（DEG free） particles.The analysis of photovoltaic properties of DSSCs based on TiO_2-DEG particles showed that the recombination of electron-hole pairs was decreased and the trapping of carries in grain boundaries restrained.It was believed that the photoelectrode fabricated with the as-prepared TiO_2 nanoparticles improved the loading amount of dye sensitizers（N719）.and enhanced the photocurrent of the DSSCs.As a result,the TiO_2-DEG particle based cells achieved a photo-to-electricity conversion efficiency（η） of 7.90%,which is higher than 7.53%for the cell based on TiO2（DEG free） and 6.59%for the one fabricated with P25.展开更多
We report a facile method for the fabrication of TiO2 nanofiber-nanoparticle composite （FP） via. simulta- neous electrospraying and electrospinning for dye-sensitized solar cell （DSC） applications. The loading of ...We report a facile method for the fabrication of TiO2 nanofiber-nanoparticle composite （FP） via. simulta- neous electrospraying and electrospinning for dye-sensitized solar cell （DSC） applications. The loading of nanoparticles on the fibers is controlled by varying their feed rates during electrospinning. The FP composites having three different particle loading are prepared by the methodology and the FP with the highest particle loading （denoted as FP-3 in the manuscript） showed the best overall efficiency of 9.15% in comparison to the other compositions of the FP （FP-2, 8.15% and FP-1, Z51%, respectively） and nanofibers （F） and nanoparticles （P） separately （7.21 and 7.81, respectively）. All the material systems are characterized by spec- troscopy, microscopy, surface area measurements and the devices are characterized by current-voltage （I-V）, incident photon-to-current conversion efficiency （IPCE）, electrochemical impedance measurements, etc. I-V, dye-loading and reflectance measurements throw light on the overall performance of the DSC devices.展开更多
A bi-layer photoanode for dye-sensitized solar cell(DSSC) was fabricated, in which TiO_2 hollow spheres(THSs) were designed as a scattering layer and P25/multi-walled carbon nanotubes(MWNTs) as an under-layer. The THS...A bi-layer photoanode for dye-sensitized solar cell(DSSC) was fabricated, in which TiO_2 hollow spheres(THSs) were designed as a scattering layer and P25/multi-walled carbon nanotubes(MWNTs) as an under-layer. The THSs were synthesized by a sacrifice template method and showed good light scattering ability as an over-layer of the photoanode. MWNTs were mixed with P25 to form an under-layer of the photoanode to improve the electron transmission ability of the photoanode. The power conversion efficiency of this kind of DSSC with bi-layer was enhanced to 5.13 %,which is 14.25 % higher than that of pure P25 DSSC.Graphical Abstract A bi-layer composite photoanode based on P25/MWNTs-THSs with improved light scattering and electron transmission, which will provide a new insight into fabrication and structure design of highly efficient dyesensitized solar cells.展开更多
YiO2 nanorods have been prepared on ITO substrates by dc reactive magnetron sputtering technique. The hydroxyl groups have been introduced on the nanorods surface. The structure and the optical properties of these nan...YiO2 nanorods have been prepared on ITO substrates by dc reactive magnetron sputtering technique. The hydroxyl groups have been introduced on the nanorods surface. The structure and the optical properties of these nanorods have been studied. The dye-sensitized solar cells （DSSCs） have been assembled using these TiO2 nanorods as photoelectrode. And the effect of the hydroxyl groups on the properties of the photoelectric conversion of the DSSCs has been studied.展开更多
The screen-printed nanoporous TiO2 thin film was employed to fabricate dye-sensitized solid-state solar cells using CuI as hole-transport materials. The solar cell based on nanoporous TiO2 thin film with large pores f...The screen-printed nanoporous TiO2 thin film was employed to fabricate dye-sensitized solid-state solar cells using CuI as hole-transport materials. The solar cell based on nanoporous TiO2 thin film with large pores formed by the addition of polystyrene balls with diameter of 200 nm to the TiO2 paste exhibits photovoltaic performance enhancement, which is attributed to the good contact of CuI with surface of dye-sensitized thin film due to easy penetration of CuI in the film with large pores.展开更多
Mesoporous TiO2 （m-TiO2） nanoparticles were used to prepare the porous film electrodes for dye-sensitized solar cells, and a second metal oxide （MgO, ZnO, A1203, or NiO） modifi- cation was carried out by dipping t...Mesoporous TiO2 （m-TiO2） nanoparticles were used to prepare the porous film electrodes for dye-sensitized solar cells, and a second metal oxide （MgO, ZnO, A1203, or NiO） modifi- cation was carried out by dipping the m-TiO2 electrode into their respective nitrate solution followed by annealing at 500 ℃. Experimental results indicated that the above second metal oxide modifications on m-TiO2 electrode are shown in all cases to act as barrier layer for the interracial charge transfer processes, but film electron transport and interfacial charge recombination characteristics under applied bias voltage were dependent significantly on the existing states and kinds of these second metal oxides. Those changes based on sec- ond metal oxide modifications showed good correlation with the current-voltage analyses of dye-sensitized solar cell, and all modifications were found to increase the open-circuit photo- voltage in various degrees, while the MgO, ZnO, and NiO modifications result in 23%, 13%, and 6% improvement in cell conversion efficiency, respectively. The above observations indi- cate that controlling the charge transport and recombination is very important to improve the photovoltaic performance of TiO2-based solar cell.展开更多
A dye-sensitized nanocrystalline TiO 2 solar cell(DYSC) was assembled, of which counter electrode was modified already by platinum, nickel and carbon. It was found that the DYSC had better photoelectric performanc...A dye-sensitized nanocrystalline TiO 2 solar cell(DYSC) was assembled, of which counter electrode was modified already by platinum, nickel and carbon. It was found that the DYSC had better photoelectric performance when the electrode was modified by platinum than by nickel and carbon. The influence of the incidence light wavelength on the incidence monochromatic photoelectric conversion efficiency(IPCE) was investigated. The result shows that the IPCE mainly depends on the short-circuit current density(I SC) of a DYSC, and the IPCE reaches 48.32% under the irradiation with the wavelength of 560 nm when the counter electrode of a DYSC was modified by platinum. The influence of incident light intensity on the photoelectric properties of a DYSC was also investigated. It was found that the I SC and open-circuit voltage(V OC) increased and the fill factor(f f) of the DYSC decreased with the increase of the incident light intensity.展开更多
Spherical TiO2 particles (60 nm) were obtained by using a Triton X-100. The surfactant was employed in two stages, i.e., in the hydrolysis of TiCl4 and then in the precipitation of the corresponding Ti (IV) polymers. ...Spherical TiO2 particles (60 nm) were obtained by using a Triton X-100. The surfactant was employed in two stages, i.e., in the hydrolysis of TiCl4 and then in the precipitation of the corresponding Ti (IV) polymers. The advantages of such spherical TiO2 particles were examined in terms of photovoltaic characteristics of a dye-sensitized solar cell (DSSC) using Orange IV dye as sensitizer. Significantly higher overall solar energy conversion efficiency was obtained for a DSSC using the film of these spherical TiO2 particles, compared with that of a cell using a TiO2 film prepared without surfactant.展开更多
Dye-sensitized solar cells (DSSCs) with ZnO spin-coated TiO2 photo-electrodes are compared to DSSC with a bare TiO2 photo-electrode. It is demonstrated that the deposited ZnO of controlled amount, by varying the precu...Dye-sensitized solar cells (DSSCs) with ZnO spin-coated TiO2 photo-electrodes are compared to DSSC with a bare TiO2 photo-electrode. It is demonstrated that the deposited ZnO of controlled amount, by varying the precursor concentration in the coating sol, can indeed enhance the performance of the DSSC. The measured power conversion efficiency shows a maximum around the precursor concentration 0.1 M and falls down sharply to 0% beyond this point. The results are interpreted on the basis of two competing factors: At ZnO concentrations less than 0.1 M, the formation of an energy barrier increases the photocurrent by reducing the rate of interfacial back-recombination. At ZnO concentrations greater than 0.1 M, the screening of the TiO2 film by thicker ZnO layers decreases the photocurrent through the reduction of TiO2 dye-adsorption efficiency.展开更多
Films of titanium oxide nanocrystalline particles (P25) were deposited using an electrophoretic deposition. The film’s characteristics were tuned for applications in dye-sensitized solar cells. Electrophoretic deposi...Films of titanium oxide nanocrystalline particles (P25) were deposited using an electrophoretic deposition. The film’s characteristics were tuned for applications in dye-sensitized solar cells. Electrophoretic deposition allows control of film characteristics such as porosity and thickness by changing deposition parameters, such as the electric field and deposition time. To increase the efficiency of the dye-sensitized solar cells with films created using electrophoretic deposition, the problem of an electrolyte contamination in the film, which occurred during deposition, was addressed. With the proper chemical post treatment, efficiency of 2.93% with fill factor of 0.55 was obtained when the films were annealed at 450℃. A low annealing temperature of 150℃ resulted in efficiencys of 1.99% with fill factor of 0.68. When the P25 was replaced by hydrothermally fabricated titanium oxide nanocrystalline particles, efficiency of 4.91% with fill factor of 0.55 was obtained.展开更多
基金supported by the Major State Basic Research Development Program of China (No.2006CB202605)the National Natural Science Foundation of China (No.50473055)
文摘The ZnO-modified TiO2 electrode was prepared by adding Zn（CH3COO）2·2H2O to the TiO2 colloid during the sol-gel production process, and was used in dye-sensitized solar cells （DSCs）. The open circuit voltage （Voc） and fill factor （if） of the cells were improved sig- nificantly. The performances of the ZnO-modified TiO2 electrode such as dark current, transient photocurrent, impedance, absorption spectra, and fiat band potential （Vfb） were investigated. It is found that the interface charge recombination impedance increases and Vfb shifts about 200 mV toward the cathodic potential. The effect mechanism of ZnO modification on the performance of DSCs may be that ZnO occupies the surface states of the TiO2 film.
基金This research was funded by National Natural Science Foundation of China (Grant No. 21676099)the Fundamental Research Funds for the Central Universities, South China University of Technology
文摘Photocatalytic oxidation desulfurization has become a research hotspot in recent years because of mild reaction conditions, less energy consumption and high selectivity. In this paper, TiO2 was loaded onto SBA-15 molecular sieves and sensitized with organic dyes(2, 9-dichloroquinacridone, DCQ) to extend its spectral response range from ultraviolet light to visible light. The catalyst DCQ-X%TiO2@SBA-15 was characterized by BET measurements, X-ray diffraction, Fourier transform infrared spectroscopy and Ultraviolet-visible diffuse reflection spectra, and then it was applied for photocatalytic oxidation desulfurization of gasoline. The effects of different catalytic systems, TiO2 concentration, catalyst dosage, and different model sulfur compounds on catalytic desulfurization performance were investigated. Experimental results show that DCQ-TiO2@SBA-15 has a better performance than the unsensitized TiO2@SBA-15, and the desulfurization rate can reach up to 96.1% in a reaction time of 90 min.
文摘Titanium tetrachloride (TiCl4) treatment was employed to TiO2 coating deposited on fluoride-doped tin oxide (FTO) conducting glass and indium oxide doped tin oxide (ITO) conducting glass, respectively. The nano-crystalline TiO2 coating was deposited using a composite powder composed of polyethylene glycol (PEG) and 25 nm TiO2 particles by vacuum cold spraying (VCS) process. A commercial N-719 dye was used to adsorb on the surface of TiO2 coating to prepare TiO2 electrode, which was applied to assemble dye-sensitized solar cell (DSC). The cell performance was measured under simulated solar light at an intensity of 100 mW·cm-2. Results show that with an FTO substrate the DSC composed of a VCS TiO2 electrode untreated by TiCl4 gives a short-circuit current density of 13.1 mA·cm-2 and an open circuit voltage of 0.60 V corresponding to an overall conversion efficiency of 4.4%. It is found that after TiCl4 treatment to the VCS TiO2 electrode with an FTO substrate, the short circuit current density of the cell increases by 31%, the open-circuit voltage increases by 60 mV and a higher conversion yield of 6.5% was obtained. However, when an ITO substrate is used to deposit TiO2 coating by VCS, after TiCl4 treatment, the conversion efficiency of the assembled cell reduces slightly due to corrosion of the conducting layer on the ITO glass by TiCl4.
基金the financial support of the project from the National Natural Science Foundation of China(No.51202139)the Specialized Research Fund for the Doctoral Program of Higher education(No.20123108120022)+2 种基金the Natural Science Foundation of Shanghai(Nos. 12ZR1443900 and 14ZR1416400)the Special Research Foundation for Training and Selecting Outstanding Young Teachers of Universities in Shanghai(No.ZZSD12041)the Innovation Foundation of Shanghai University
文摘Single-crystalline anatase TiO2nanorods have been prepared by solvothermal method using tetrabutylammonium hydroxide（TBAH） as a morphology controlling agent.The obtained TiO2nanorods are dominated by a large percentage of {010} facets.The power conversion efficiency of dye-sensitized solar cell（DSSC） based on anatase TiO2nanorods（8.66%） exhibits a significant improvement（35%） compared to that of P25 TiO2（5.66%）.The high performance of the anatase TiO2nanorods solar cell is ascribed to their large percent of exposed {010} facets as well as balancing their surface areas and sizes.
基金Project supported by the Polish Ministry of Science and Higher Education (N N204 023538)
文摘Modified with gadolinium-containing layer, nanoporous titania electrode and its application in dye-sensitized solar cells were reported. The electrode prepared was characterized with UV-Vis and X-ray diffraction （XRD） techniques. The amount of gadolinium was measured with inductively coupled plasma-optical emission spectrometry （ICP-OES） experiments. The modified electrode showed reduced N3 dye adsorption ability, but increased light conversion efficiency in comparison with the non-modified electrode. The overall conversion efficiencies, determined under 400 W/m2 irradiation with tungsten-halogen lamp at room temperature, were 0.55% for non-modified and 0.74% for modified electrodes.
基金Support of this research by the National Science Council of Taiwan under Grant No. NSC 100-2221-E-006-214partial support under Contract No. 101-D0204-6 by the Bureau of Energy, Ministry of Economic Affairs of Taiwanthe LED Lighting Research Center, NCKU
文摘Three different types of TiO2 nano powders were synthesized by a solution combustion synthesis （SCS） method using three different fuels and for comparison, another type of Ti2 nano powder was synthesized by calcination of titanyl hydroxide. These TiO2 nano powders were used to fabricate photoelectrodes for the dye-sensitized solar cell （DSSC） and their performance was compared to that of the DSSC fabricated with Degussa P25 TiO2. The results showed that the SCS TiO2 could work well as photoelectrode for DSSC. The SCS TiO2 contained impurities of C and/or S, thus exhibiting visible light absorption and reduced band gap. The open circuit voltage and the fill factor both varied little among the various TiO2 and thus both had little effect on the photoelectrical conversion efficiency （η）. However, the variation of r/was seen to be in quite a good agreement with that of the short circuit current （Isc）, suggesting that r/was dominated by Isc. lsc was found to be enhanced by light scattering effect due to the presence of large particles but reduced by high impurity content due to an increase in electron transfer resistance. In addition, the specific surface area of the powders was found to be an important factor affecting the Isc and thus the η.
基金Supported by Self-Determined Research Funds of Huazhong Normal University from the Colleges’ Basic Research and Operation of Ministry of Education (CCNU09A02011)
文摘In this study,TiO2@MgO core-shell film was obtained by using a simple chemical bath deposition method to coat a thin MgO film around TiO2 nanoparticles. The core-shell configuration was characterized by X-ray diffractometer (XRD),scanning elec-tron microscopy (SEM),energy dispersive X-ray spectroscopy (EDX),and high-resolution transmission electron microscopy (HRTEM). Lattice fringes were observed for the TiO2 particles,and the MgO shell showed an amorphous structure,revealing a clear distinction between the core and shell materials. Applying the core-shell film as photoanode to the dye-sensitized solar cells (DSSCs),it shows a superior performance compared to the pure TiO2 electrode. Under the illumination of simulated sunlight (75 mW-cm-2),the short circuit photocurrent (Jsc),the open circuit photovoltage (Voc),and the fill factor (fF) are 8.80 mA-cm-2,646 mV,and 0.69,respectively,and the conversion efficiency (η) in-creased by 21.8% (from 4.32% to 5.26%) when dipping for opti-mum condition.
基金supported by the National Natural Science Foundation of China (Nos. 51572072 and 11204070)the Fundamental Research Funds for the Central Universities (No. 2014-Ia-028)financially supported by State Key Laboratory of Advanced Technology for Materials Synthesis and Processing (No. 2016-KF-13)
文摘In this work, a three-layer TiO2 composite film consisting of flower-like TiO2 （Flo-TiO2） as overlayer, TiOa nanotube arrays as interlayer and TiO2 nanoparticle （P25） as underlayer was fabricated as the photoelectrode of dyesensitized solar cells （DSSCs）. Due to the introduction of Flo-TiO2, the three-layer composite film has strong lightscattering ability. Then, we have investigated and compared the photoelectric conversion properties of DSSCs based on three-layer structure （P25/TNT arrays/Flo-TiO2） photoelectrode and double-layer film （P25/TNT arrays） photoelectrode. It is found that DSSCs based on three-layer structure exhibit a high power conversion efficiency of 6.48% compared with the DSSCs composed of double-layer film （5.11%）.
基金Project supported by the Fundamental Research Funds for the Central Universities,China(Grant No.2013XK07)
文摘TiO2 is a wide band gap semiconductor with important applications in photovoltaic cells. Vertically aligned Tit2 nanorod arrays （NRs） are grown on the fluorine-doped tin oxide （FTO） substrates by a multicycle hydrothermal synthesis process. The samples are characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, high-resolution transmission electron microscopy （HRTEM）, and selected-area electron diffraction （SAED）. It is found that dye-sensitized solar cells （DSSCs） assembled by the as-prepared Tit2 single-crystal NRs exhibit different trends under the condition of different nucleation and growth concentrations. Optimum cell performance is obtained with high nucleation concentration and low growth cycle concentration. The efficiency enhancement is mainly attributed to the improved specific surface area of the nanorod.
基金supported by The National Natural Science Foundation of China(No.B59883004)partially supported by the Research Institute of Innovative Technology for the Earth(RITE),Japan.
文摘A dye-sensitized TiO2 solid solar cell, which contains poly(4-vinylphenyloxy-methyltriphenylamine) in hole transport layer (HTL) doped with LiSCN and methyl-hexyl-imidazolium iodide (MHIml), was prepared. The solar cell shows that the conversion efficiency is 0.59%, Jsc is 3.03mA/cm2, and V^ is 0.53V at 1 sun light intensity.
基金supported by National Natural Science Foundation of China(No.21476162)China International Science and Technology Project(Nos.2012DFG41980,S2016G3413)
文摘The performance of dye-sensitized solar cells（DSSCs） consisting of anatase TiO_2 nanoparticles that were synthesized via a hydrothermal method was studied.The synthesized TiO_2 nanoparticles were characterized by X-ray diffraction（XRD）,nitrogen sorption analysis,scanning electron microscopy（SEM）,high resolution transmission electron microscopy（HRTEM）,and UV-vis spectroscopy.Then the J-Vcurve,electrochemical impedance spectroscopy（EIS）,and open-circuit voltage decay（OCVD） measurement were applied to evaluate the photovoltaic performance of DSSCs.Compared with the commercial TiO_2nanoparticles（P25）,the synthesized-TiO_2 nanoparticles showed better performance.By adding diethylene glycol（DEG） before the hydrothermal process,the synthesized TiO_2 nanoparticles（hereafter referred to as TiO_2-DEG particles） shows narrower size distribution,larger specific surface area,higher crystallinity,and less surface defects than TiO_2（DEG free） particles.The analysis of photovoltaic properties of DSSCs based on TiO_2-DEG particles showed that the recombination of electron-hole pairs was decreased and the trapping of carries in grain boundaries restrained.It was believed that the photoelectrode fabricated with the as-prepared TiO_2 nanoparticles improved the loading amount of dye sensitizers（N719）.and enhanced the photocurrent of the DSSCs.As a result,the TiO_2-DEG particle based cells achieved a photo-to-electricity conversion efficiency（η） of 7.90%,which is higher than 7.53%for the cell based on TiO2（DEG free） and 6.59%for the one fabricated with P25.
基金supported by Ministry of New and Renewable Energy(MNRE)the Solar Energy Research Initiative(SERI),respectively.of Govt.of India
文摘We report a facile method for the fabrication of TiO2 nanofiber-nanoparticle composite （FP） via. simulta- neous electrospraying and electrospinning for dye-sensitized solar cell （DSC） applications. The loading of nanoparticles on the fibers is controlled by varying their feed rates during electrospinning. The FP composites having three different particle loading are prepared by the methodology and the FP with the highest particle loading （denoted as FP-3 in the manuscript） showed the best overall efficiency of 9.15% in comparison to the other compositions of the FP （FP-2, 8.15% and FP-1, Z51%, respectively） and nanofibers （F） and nanoparticles （P） separately （7.21 and 7.81, respectively）. All the material systems are characterized by spec- troscopy, microscopy, surface area measurements and the devices are characterized by current-voltage （I-V）, incident photon-to-current conversion efficiency （IPCE）, electrochemical impedance measurements, etc. I-V, dye-loading and reflectance measurements throw light on the overall performance of the DSC devices.
基金the support provided by the National High Technology Research and Development Program 863 (No.2006AA05Z417)Science and Technology Platform Construction Project of Dalian (2010-354)+4 种基金the Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning (No.2013-70)‘‘Shu Guang’’ project supported by Shanghai Municipal Education Commission and Shanghai Education Development Foundation (No.13SG55)National Natural Science Foundation of China (NSFC) (No.61376009)Science and Technology Commission of Shanghai Municipality (No.14YF1410500)Shanghai Young Teacher Supporting Foundation (No.ZZEGD14011)
文摘A bi-layer photoanode for dye-sensitized solar cell(DSSC) was fabricated, in which TiO_2 hollow spheres(THSs) were designed as a scattering layer and P25/multi-walled carbon nanotubes(MWNTs) as an under-layer. The THSs were synthesized by a sacrifice template method and showed good light scattering ability as an over-layer of the photoanode. MWNTs were mixed with P25 to form an under-layer of the photoanode to improve the electron transmission ability of the photoanode. The power conversion efficiency of this kind of DSSC with bi-layer was enhanced to 5.13 %,which is 14.25 % higher than that of pure P25 DSSC.Graphical Abstract A bi-layer composite photoanode based on P25/MWNTs-THSs with improved light scattering and electron transmission, which will provide a new insight into fabrication and structure design of highly efficient dyesensitized solar cells.
文摘YiO2 nanorods have been prepared on ITO substrates by dc reactive magnetron sputtering technique. The hydroxyl groups have been introduced on the nanorods surface. The structure and the optical properties of these nanorods have been studied. The dye-sensitized solar cells （DSSCs） have been assembled using these TiO2 nanorods as photoelectrode. And the effect of the hydroxyl groups on the properties of the photoelectric conversion of the DSSCs has been studied.
基金the financial support of this work by the Major State Basic Research Development Program(No.2006CB202605)High-Tech Research and Development of China Program(No.2007AA05Z439)+1 种基金the National Nature Science Foundation of China(No.50221201)Innovative Foundation of the Center for Molecular Science,Chinese Academy of Sciences(No.CMS-CX200718).
文摘The screen-printed nanoporous TiO2 thin film was employed to fabricate dye-sensitized solid-state solar cells using CuI as hole-transport materials. The solar cell based on nanoporous TiO2 thin film with large pores formed by the addition of polystyrene balls with diameter of 200 nm to the TiO2 paste exhibits photovoltaic performance enhancement, which is attributed to the good contact of CuI with surface of dye-sensitized thin film due to easy penetration of CuI in the film with large pores.
文摘Mesoporous TiO2 （m-TiO2） nanoparticles were used to prepare the porous film electrodes for dye-sensitized solar cells, and a second metal oxide （MgO, ZnO, A1203, or NiO） modifi- cation was carried out by dipping the m-TiO2 electrode into their respective nitrate solution followed by annealing at 500 ℃. Experimental results indicated that the above second metal oxide modifications on m-TiO2 electrode are shown in all cases to act as barrier layer for the interracial charge transfer processes, but film electron transport and interfacial charge recombination characteristics under applied bias voltage were dependent significantly on the existing states and kinds of these second metal oxides. Those changes based on sec- ond metal oxide modifications showed good correlation with the current-voltage analyses of dye-sensitized solar cell, and all modifications were found to increase the open-circuit photo- voltage in various degrees, while the MgO, ZnO, and NiO modifications result in 23%, 13%, and 6% improvement in cell conversion efficiency, respectively. The above observations indi- cate that controlling the charge transport and recombination is very important to improve the photovoltaic performance of TiO2-based solar cell.
基金Supported by the National Natural Science Foundation of China(No. 5 0 0 82 0 0 3,5 0 372 0 2 2 ) and the Natural ScienceFoundation of Fujian Province,China(No. 2 0 0 1I0 0 6,E0 2 10 0 2 3)
文摘A dye-sensitized nanocrystalline TiO 2 solar cell(DYSC) was assembled, of which counter electrode was modified already by platinum, nickel and carbon. It was found that the DYSC had better photoelectric performance when the electrode was modified by platinum than by nickel and carbon. The influence of the incidence light wavelength on the incidence monochromatic photoelectric conversion efficiency(IPCE) was investigated. The result shows that the IPCE mainly depends on the short-circuit current density(I SC) of a DYSC, and the IPCE reaches 48.32% under the irradiation with the wavelength of 560 nm when the counter electrode of a DYSC was modified by platinum. The influence of incident light intensity on the photoelectric properties of a DYSC was also investigated. It was found that the I SC and open-circuit voltage(V OC) increased and the fill factor(f f) of the DYSC decreased with the increase of the incident light intensity.
文摘Spherical TiO2 particles (60 nm) were obtained by using a Triton X-100. The surfactant was employed in two stages, i.e., in the hydrolysis of TiCl4 and then in the precipitation of the corresponding Ti (IV) polymers. The advantages of such spherical TiO2 particles were examined in terms of photovoltaic characteristics of a dye-sensitized solar cell (DSSC) using Orange IV dye as sensitizer. Significantly higher overall solar energy conversion efficiency was obtained for a DSSC using the film of these spherical TiO2 particles, compared with that of a cell using a TiO2 film prepared without surfactant.
文摘Dye-sensitized solar cells (DSSCs) with ZnO spin-coated TiO2 photo-electrodes are compared to DSSC with a bare TiO2 photo-electrode. It is demonstrated that the deposited ZnO of controlled amount, by varying the precursor concentration in the coating sol, can indeed enhance the performance of the DSSC. The measured power conversion efficiency shows a maximum around the precursor concentration 0.1 M and falls down sharply to 0% beyond this point. The results are interpreted on the basis of two competing factors: At ZnO concentrations less than 0.1 M, the formation of an energy barrier increases the photocurrent by reducing the rate of interfacial back-recombination. At ZnO concentrations greater than 0.1 M, the screening of the TiO2 film by thicker ZnO layers decreases the photocurrent through the reduction of TiO2 dye-adsorption efficiency.
文摘Films of titanium oxide nanocrystalline particles (P25) were deposited using an electrophoretic deposition. The film’s characteristics were tuned for applications in dye-sensitized solar cells. Electrophoretic deposition allows control of film characteristics such as porosity and thickness by changing deposition parameters, such as the electric field and deposition time. To increase the efficiency of the dye-sensitized solar cells with films created using electrophoretic deposition, the problem of an electrolyte contamination in the film, which occurred during deposition, was addressed. With the proper chemical post treatment, efficiency of 2.93% with fill factor of 0.55 was obtained when the films were annealed at 450℃. A low annealing temperature of 150℃ resulted in efficiencys of 1.99% with fill factor of 0.68. When the P25 was replaced by hydrothermally fabricated titanium oxide nanocrystalline particles, efficiency of 4.91% with fill factor of 0.55 was obtained.
