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1.
Poly(n‐isopropylacrylamide) (PNIPAAm) and its nanocomposite with exfoliated montmorillonite (MMT) were prepared by soap‐free emulsion polymerization and individually applied to gel the electrolyte systems for the dye‐sensitized solar cells (DSSCs). Each exfoliated MMT nanoplatelet had a thickness of ~ 1 nm, carried ~ 1.8 cation/nm2, and acted like a two‐dimensional electrolyte. The DSSC with the LiI/I2/tertiary butylpyridine electrolyte system gelled by this polymer nanocomposite had higher short‐circuit current density (Jsc) compared to that gelled by the neat PNIPAAm. The former has a Jsc of 12.6 mA/cm2, an open circuit voltage (Voc) of 0.73 V, and a fill factor (FF) of 0.59, which harvested 5.4% electricity conversion efficiency (η) under AM 1.5 irradiation at 100 mW/cm2, whereas the latter has Jsc = 7.28 mA/cm2, Voc = 0.72 V, FF = 0.60, and η = 3.17%. IPCE of the nanocomposite‐gelled DSSC were also improved. Electrochemical impedance spectroscopy of the DSSCs revealed that the nanocomposite‐gelled electrolytes significantly decreased the impedances in three major electric current paths of DSSCs, that is, the resistance of electrolytes and electric contacts, impedance across the electrolytes/dye‐coated TiO2 interface, and Nernstian diffusion within the electrolytes. The results were also consistent with the increased molar conductivity of nanocomposite‐gelled electrolytes. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 47–53, 2008  相似文献   

2.
Discotic mesogenic molecules viz., hexahexylthiotriphenylene (HHTT) and hexahexyloxytriphenylene were applied, for the first time, as iodine-free redox electrolyte in dye-sensitised solar cells (DSSCs). The cell shows open circuit voltage (Voc) of 0.95 V, short circuit current density (Jsc) of 0.534 mA/cm2, fill factor 88.24% and overall power conversion efficiency (η) 0.45% in a typical fluorine doped tin oxide/TiO2/N719/HHTT/Pt DSSC configuration. Scanning electron microscopy was used to study surface profile of electrolytes while electrochemical impedance spectroscopy was used to understand the electrochemical behaviour of electrolytes. The photovoltaic parameters were measured under standard conditions using Oriel solar simulator class AAA. These first results demonstrate the potential of the discotic molecules as charge transporter and mediator and show promise to be used in iodine-free DSSCs.  相似文献   

3.
This work is concerned with the growth of TiO2 nanostructures as photovoltaic materials of dyesensitized solar cell (DSSC) via phase liquid deposition technique treated with CTAB surfactant. This work investigates the influence of organic dyes, N719, N3 and Z907 as photosensitizer on the photovoltaic parameters of TiO2 nanostructures dye-sensitized solar cells (DSSCs). It also highlights the effect of the concentration of the best dye, N719 on the performance of the cell. The platinum films as counter electrode of the DSSC were prepared by sputtering platinum pellet on ITO substrate. The redox couple of the electrolyte utilized in the DSSC was iodide/triiodide. The cell sensitized with N719 dye demonstrated the best performance compared with the cell sensitized with another two dyes, N3 and Z907. This is due to N719 dye possess the highest optical absorption in visible region. The cell sensitized with 0.8 mM N719 dye performs the highest short-circuit current density, J sc and power conversion efficiency, η since it posses the highest absorption in visible region. The DSSC utilizing 0.8 mM N719 dye demonstrated the highest J sc and η of 6.48 mA cm?2 and 1.69%, respectively.  相似文献   

4.
Organic dyes that consist of a [2.2]paracyclophane moiety between a triphenylamine donor group and a cyanoacrylic acid acceptor group have exhibited considerably high values of open-circuit voltage (Voc) in the range of 0.69–0.74 V. In an experiment that involved using an ion liquid electrolyte (E2 electrolyte), the values of Voc were increased to 0.03–0.04 V because of a decrease in the concentration of LiI. A typical device demonstrated a maximal incident photon-to-current conversion efficiency (IPCE) of 60% in the region of 350–475 nm, a short-circuit photo current density (Jsc) of 8.80 mA cm−2, an open-circuit photovoltage (Voc) of 0.74 V, and a fill factor (FF) of 0.65, corresponding to an overall conversion efficiency of 4.24% of CPG2b. The photophysical properties were analyzed using a time-dependent density functional theory (TDDFT) model with the M062X functional.  相似文献   

5.
A series of simple phenothiazine‐based dyes, namely, TP , EP , TTP , ETP , and EEP have been developed, in which the thiophene (T), ethylenedioxythiophene (E), their dimers, and mixtures are present to modulate dye aggregation, charge recombination, and dye regeneration for highly efficient dye‐sensitized solar cell (DSSC) applications. Devices sensitized by the dyes TP and TTP display high power conversion efficiencies (PCEs) of 8.07 (Jsc=15.2 mA cm?2, Voc=0.783 V, fill factor (FF)=0.679) and 7.87 % (Jsc=16.1 mA cm?2, Voc=0.717 V, FF=0.681), respectively; these were measured under simulated AM 1.5 sunlight in conjunction with the I?/I3? redox couple. By replacing the T group with the E unit, EP ‐based DSSCs had a slightly lower PCE of 7.98 % with a higher short‐circuit photocurrent (Jsc) of 16.7 mA cm?2. The dye ETP , with a mixture of E and T, had an even lower PCE of 5.62 %. Specifically, the cell based on the dye EEP , with a dimer of E, had inferior Jsc and Voc values and corresponded to the lowest PCE of 2.24 %. The results indicate that the photovoltaic performance can be finely modulated through structural engineering of the dyes. The selection of T analogues as donors can not only modulate light absorption and energy levels, but also have an impact on dye aggregation and interfacial charge recombination of electrons at the interface of titania, electrolytes, and/or oxidized dye molecules; this was demonstrated through DFT calculations, electrochemical impedance analysis, and transient photovoltage studies.  相似文献   

6.
Three electron donor‐?? bridge‐electron acceptor (D‐π‐A) organic dyes bearing two carboxylic acid groups were applied to dye‐sensitized solar cells (DSSC) as sensitizers, in which one triphenylamine or modified triphenylamine and two rhodanine‐3‐acetic acid fragments act as D and A, respectively. It was found that the introduction of t‐butyl or methoxy group in the triphenylamine subunit could lead to more efficient photoinduced intramolecular charge transfer, thus improving the overall photoelectric conversion efficiency of the resultant DSSC. Under global AM 1.5 solar irradiation (73 mW·cm?2), the dye molecule based on methoxy‐substituted triphenylamine achieved the best photovoltaic performance: a short circuit photocurrent density (Jsc) of 12.63 mA·cm?2, an open circuit voltage (Voc) of 0.55 V, a fill factor (FF) of 0.62, corresponding to an overall efficiency (η) of 5.9%.  相似文献   

7.
A series of heteroleptic bis(tridentate) RuII complexes featuring N^C^N‐cyclometalating ligands is presented. The 1,2,3‐triazole‐containing tridentate ligands are readily functionalized with hydrophobic side chains by means of click chemistry and the corresponding cyclometalated RuII complexes are easily synthesized. The performance of these thiocyanate‐free complexes in a dye‐sensitized solar cell was tested and a power conversion efficiency (PCE) of up to 4.0 % (Jsc=8.1 mA cm?2, Voc=0.66 V, FF=0.70) was achieved, while the black dye ((NBu4)3[Ru(Htctpy)(NCS)3]; Htctpy=2,2′:6′,2′′‐terpyridine‐4′‐carboxylic acid‐4,4′′‐dicarboxylate) showed 5.2 % (Jsc=10.7 mA cm?2, Voc=0.69 V, FF=0.69) under comparable conditions. When co‐adsorbed with chenodeoxycholic acid, the PCE of the best cyclometalated dye could be improved to 4.5 % (Jsc=9.4 mA cm?2, Voc=0.65 V, FF=0.70). The PCEs correlate well with the light‐harvesting capabilities of the dyes, while a comparable incident photon‐to‐current efficiency was achieved with the cyclometalated dye and the black dye. Regeneration appeared to be efficient in the parent dye, despite the high energy of the highest occupied molecular orbital. The device performance was investigated in more detail by electrochemical impedance spectroscopy. Ultimately, a promising RuII sensitizer platform is presented that features a highly functionalizable “click”‐derived cyclometalating ligand.  相似文献   

8.
New hemicyanine dyes ( CM101 , CM102 , CM103 , and CM104 ) in which tetrahydroquinoline derivatives are used as electron donors and N‐(carboxymethyl)‐pyridinium is used as an electron acceptor and anchoring group were designed and synthesized for dye‐sensitized solar cells (DSSCs). Compared with corresponding dyes that have cyanoacetic acid as the acceptor, N‐(carboxymethyl)‐pyridinium has a stronger electron‐withdrawing ability, which causes the absorption maximum of dyes to be redshifted. The photovoltaic performance of the DSSCs based on dyes CM101 – CM104 markedly depends on the molecular structures of the dyes in terms of the n‐hexyl chains and methoxyl. The device sensitized by dye CM104 achieved the best conversion efficiency of 7.0 % (Jsc=13.4 mA cm?2, Voc=704 mV, FF=74.8 %) under AM 1.5 irradiation (100 mW cm?2). In contrast, the device sensitized by reference dye CMR104 with the same donor but the cyanoacetic acid as the acceptor gave an efficiency of 3.4 % (Jsc=6.2 mA cm?2, Voc=730 mV, FF=74.8 %). Under the same conditions, the cell fabricated with N719 sensitized porous TiO2 exhibited an efficiency of 7.9 % (Jsc=15.4 mA cm?2, Voc=723 mV, FF=72.3 %). The dyes CM101 – CM104 show a broader spectral response compared with the reference dyes CMR101 – CMR104 and have high IPCE exceeding 90 % from 450 to 580 nm. Considering the reflection of sunlight, the photoelectric conversion efficiency could be almost 100 % during this region.  相似文献   

9.
Abstract

Alkyl substituents appended to polymers play the determining role on self-assembly and film-forming properties, and on device performance. In this work, we highlight the effects of the linear and branched flexible chains appended to the acceptor moiety (A) in D-A type copolymers. Two thieno[3,4-c]-pyrrole-4,6-dione (TPD) based copolymers PT1 and PT2 with different alkyl chains, were designed and synthesized. By comparison their UV-vis absorptions, HOMO/LUMO energy levels, as well as the characters in polymer solar cells, the influences of alkyl chains were investigated. Both copolymers showed molecular weights of 21?kDa and similar optical properties with a medium band gap of 1.93?eV, while PT2 with the branched chain exhibited a lower HOMO than that of PT1 (?5.43 vs???5.37?eV). In bulk heterojunction (BHJ) solar cells, PT1 with a linear chain presented a short circuit current (Jsc) of 6.76?mA cm?2, open circuit voltage (Voc) of 0.89?V and power conversion efficiency (PCE) of 2.92%. To the contrary, PT2 showed a Jsc of 3.53?mA cm?2, Voc of 0.99?V, delivering a relatively lower PCE of 2.05%. The result indicates that appending a linear alkyl chain to the TPD unit could sufficient enhance the Jsc value of the related polymer.  相似文献   

10.
Four new donor–acceptor type polymeric metal complexes (P1, P2, P3, and P4) with the same Cd(II) complex in side chain and different conjugated backbone structures were synthesized by Yamamoto coupling and applied in dye-sensitized solar cells (DSSCs) as photosensitizers. The photophysical, electrochemical, and thermal properties were investigated in detail, showing that conjugated backbone containing fluorene improved intramolecular charge transfer and increased generation of photocurrent. The highest power conversion efficiency of 0.56% (J sc?=?1.63?mA?cm?2, V oc?=?0.69?V, FF?=?0.50) was obtained with a DSSC based on P3 under simulated air mass 1.5 G solar irradiation, which shows a new strategy to design photosensitizers for DSSCs.  相似文献   

11.
Organic dyes that consist of an anthracene moiety between a triphenylamine donor group and a cyanoacrylic acid acceptor group displayed remarkable solar-to-energy conversion efficiency in dye-sensitized solar cells. The planar geometry of anthracene and its bulky substituents helped the dyes to form a high quality monolayer on the surface of TiO2. A typical device made with the dye AN-Bu displayed a maximal photon-to-current conversion efficiency (IPCE) 65% in the region of 350–510 nm, a short-circuit photocurrent density (Jsc) 12.78 mA cm−2, an open-circuit photovoltage (Voc) 0.73 V, and a fill factor (FF) 0.67, corresponding to an overall conversion efficiency 6.23%. In an experiment of using deoxycholic acid (DCA) as a co-absorbent, the values of Voc stayed in a similar range, yet the values of Jsc were reduced in ca. 11% due to a decrease of loading amounts. This result indicated that the quality of the dye films cannot be further improved by the adding of DCA. The photophysical properties were analyzed with the aid of a time-dependent density functional theory (TDDFT) model with the B3LYP functional.  相似文献   

12.
We synthesized three metal-free organic dyes (H11H13) consisting of a 3,6-disubstituted carbazole, benzothiadiazole, and cyanoacrylic acid. All the dyes exhibited high molar extinction coefficients and suitable energy levels for electron transfer from the electrolyte to the TiO2 nanoparticles. Under standard AM 1.5G solar irradiation, the device using dye H13 with co-adsorbed chenodeoxycholic acid (CDCA) displayed the best performance: an open-circuit voltage (Voc) of 0.71 V, a short-circuit current density (Jsc) of 12.69 mA cm−2, a fill factor (FF) of 0.71, and a power conversion efficiency (PCE) of 6.32%. The PCE was ∼79% of that for commercially available N719 cells (8.02%) under the same conditions.  相似文献   

13.
Luminescence downshifting (LDS) of light can be a practical photon management technique to compensate the narrow absorption band of high‐extinction‐coefficient dyes in dye‐sensitized solar cells (DSSCs). Herein, an optical analysis on the loss mechanisms in a reflective LDS (R‐LDS)/DSSC configuration is reported. For squaraine dye (550–700 nm absorption band) and CaAlSiN3:Eu2+ LDS material (550–700 nm emission band), the major loss channels are found to be non‐unity luminescence quantum efficiency (QE) and electrolyte absorption. By using an ideal LDS layer (QE=100 %), a less absorbing electrolyte (Co‐based), and antireflection coatings, approximately 20 % better light harvesting is obtained. If the absorption/emission band of dye/LDS is shifted to 800 nm, a maximal short‐circuit current density (Jsc) of 22.1 mA cm?2 can be achieved. By putting the LDS layer in front of the DSSC (transmissive mode), more significant loss channels are observed, and hence a lower overall efficiency than the R‐LDS configuration.  相似文献   

14.
In this paper, effects of ethylene glycol (EG) and indium tin oxide (ITO) solution on the morphology, porosity, and roughness of TiO2 film prepared by sol‐gel process were investigated and discussed. Initially, the addition of EG were used to control the viscosity of the solution and it was found to increase the pore size of TiO2 film. The various TiO2 films were investigated and characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM) and then assembled to dye‐sensitized solar cell (DSSC) to measure the photoelectric conversion efficiency. The optimum efficiencies of 1.32% with Jsc and Voc of 2.99 mA/cm2 and 0.80 V, respectively, were obtained by the TiO2 film prepared from a solution containing 20 wt% EG.  相似文献   

15.
《印度化学会志》2022,99(1):100289
This work is concerned with the comparative study of dye-sensitized solar cell (DSSC) utilizing selenium (Se) and palladium (Pd) cathode. The influence of concentration of selenium dioxide (SeO2) and palladium chloride (PdCl2) on the performance of the device has been investigated. The Se and Pd cathode have been prepared via dip coating-based multilayer deposition technique. The device using Se cathode with seven layers possesses the highest performance in term of short-circuit current density (Jsc). The photovoltaic measurement results show that the device utilizing Pd cathode demonstrates higher power conversion efficiency (η) compared with that of the device using Se cathode. The highest η of the device with Se and Pd cathode are 0.071 and 0.169%, obtained at the 0.5 ?M SeO2 and 0.60 ?M PdCl2, respectively. The Pd cathode-based device prepared with 0.60 ?M PdCl2 owns the highest η due to the lowest sheet resistance (Rs). These photovoltaic results imply single material has potential to be modified into binary or ternary cathode material in order to improve the performance of DSSC.  相似文献   

16.
The effect of 4,4′-diaminodiphenylsulfone (DADPS) as a co-additives in iodide/triiodide redox electrolyte on the performance of dye-sensitized solar cell based on the 2-cyano-3-(4-(diphenylamino)phenyl)acrylic acid (TPA) and 2-cyano-3-(2΄-(5΄,10΄,15΄,20΄- tetraphenylporphyrinato Zinc (II)yl) acrylic acid (Zn-1) dyes have been investigated. Compared withstandard electrolyte (0.1 M LiI, 0.05 M I2, 0.6 M 1-butyl-2,3-dimethylimidazolium iodide (BDMII) and TBP (0.5, 1 M)), adding 0.5 M of DADPS, as a co-additive, into the electrolyte system has caused increasing short current density (Jsc) and open-circuit potential (Voc) consequently the energy conversion (η) improved. Electrochemical impedance results indicate adsorbing of DADPS on the titanium dioxide surface leads to an increase in the lifetime (τ). Adsorbing of DADPS on the semiconductor surface retards the interfacial charge recombination that has a beneficial effect on the Voc and Jsc. The results showed that amine groups of DADPS attach to the conduction band (CB) of TiO2 film and suppress the electron recombination process and as a result, it can be applied as a promising co-additive in DSSCs.  相似文献   

17.
We have designed and synthesized highly efficient organic sensitizers with a planar thienothiophene–vinylene–thienothiophene linker. Under standard global AM 1.5 solar conditions, the JK‐113 ‐sensitized cell gave a short circuit photocurrent density (Jsc) of 17.61 mA cm?2, an open‐circuit voltage (Voc) of 0.71 V, and a fill factor (FF) of 72 %, corresponding to an overall conversion efficiency (η) of 9.1 %. The incident monochromatic photo‐to‐current conversion efficiency (IPCE) of JK‐113 exceeds 80 % over the spectral region from 400 to 640 nm, reaching its maximum of 93 % at 475 nm. The band tails off toward 770 nm, contributing to the broad spectral light harvesting. Solar‐cell devices based on the sensitizer JK‐113 in conjunction with a volatile electrolyte and a solvent‐free ionic liquid electrolyte gave high conversion efficiencies of 9.1 % and 7.9 %, respectively. The JK‐113 ‐based solar cell fabricated using a solvent‐free ionic liquid electrolyte showed excellent stability under light soaking at 60 °C for 1000 h.  相似文献   

18.
Two new benzotriazole-bridged sensitizers are designed and synthesized ( BTA-I and BTA-II ) containing a furan moiety for dye-sensitized solar cells (DSSCs). Two corresponding dyes ( BTA-III and BTA-IV ) with a thiophene spacer were also synthesized for comparison. All of these dyes performed as sensitizers for DSSCs, and the photovoltaic performance data of these benzotriazole-bridged dyes showed a high open-circuit voltage (Voc: 804–834 mV). Among the four dyes, DSSCs based on BTA-II , with a furan moiety and branched alkyl chain, showed the highest Voc (834 mV), a photocurrent density (Jsc) of 12.64 mA cm−2, and a fill factor (FF) of 0.64, corresponding to an overall conversion efficiency (η) of 6.72 %. Most importantly, long-term stability of the BTA-I , BTA-II , BTA-III , BTA-IV -based DSSCs with ionic-liquid electrolytes under 1000 h light-soaking was demonstrated, and BTA-II exhibited better photovoltaic performance of up to 5.06 % power conversion efficiency.  相似文献   

19.
A series of new-type of donor-π-acceptor dyes (TCT-1-6) utilizing 1,3,5-triazine as π spacers were synthesized. These dyes were characterized by 1H NMR, ESI-MS, EA, and X-ray crystallography. Their photovoltaic performances were also investigated. An overall photon-to-electron conversion efficiency of 1.8% was achieved with the DSSC based on the dye TCT-1(Jsc = 3.33 mA/cm2, Voc = 757 mV, FF = 71.8%) under AM 1.5G illumination (100 mW/cm2).  相似文献   

20.
In this work, a benzenedinitrile functionalized monomer, 2‐methyl‐acrylic acid 6‐(3,4‐dicyano‐phenoxy)‐hexyl ester, was successfully polymerized via the reversible addition‐fragmentation chain transfer method. The polymerization behavior conveyed the characteristics of “living”/controlled radical polymerization: the first‐order kinetics, linear increase of number‐average molecular weight with monomer conversion, narrow molecular weight distribution, and successful chain‐extension experiment. The soluble Zn(II) phthalocyanine (Pc)‐containing (ZnPc) polymers were achieved by post‐polymerization modification of the obtained polymers. The Zn(II) phthalocyanine‐functionalized polymer was characterized by FTIR, UV–vis, fluorescence, atomic absorption spectroscopy, and thermogravimetric analysis. The potential application of above ZnPc‐functionalized polymer as electron donor material in bulk heterojunction organic solar cell was studied. The device with ITO/PEDOT:PSS/ZnPc‐Polymer/PC61BM/LiF/Al structure provided a power conversion efficiency of 0.014%, fill factor of 0.24, open circuit voltage (Voc) of 0.21 V, and short‐circuit current (Jsc) of 0.28 mA/cm2. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 691–698  相似文献   

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