scholarly journals Influence of Electrolyte Refreshing on the Photoelectrochemical Performance of Fiber-Shaped Dye-Sensitized Solar Cells

2012 ◽  
Vol 2012 ◽  
pp. 1-8
Author(s):  
Zhibin Lv ◽  
Hongwei Wu ◽  
Xin Cai ◽  
Yongping Fu ◽  
Dan Wang ◽  
...  

Given the convenient sealing of fiber-shaped dye-sensitized solar cells (FDSSCs), the electrolyte refreshing effect on the photo-electrochemical performance of FDSSCs was studied. The electron transport and interfacial recombination kinetics were also systematically investigated by electrochemical impedance spectroscopy. With increased electrolyte refreshing times from 0 to 10, the open-circuit voltage (Voc) and fill factor (FF) increased, whereas the photocurrent density (Jsc) and power conversion efficiency (PCE) significantly decreased. The increasedVocwas mainly ascribed to the electron recombination resistance (Rct, WE) at the TiO2/electrolyte interface and electron lifetime. The decreasedJscand PCE were due to dye desorption and the increase of series resistance. Further investigation proved that Li+played a vital role in increasingVocas electrolyte refreshing and Li+had more significant impact than TBP (tert-butyl pyridine) on maintaining highVoc.

MRS Advances ◽  
2019 ◽  
Vol 4 (08) ◽  
pp. 481-489
Author(s):  
Jihun Kim ◽  
Horim Lee ◽  
Dong Young Kim ◽  
Sehyun Kim ◽  
Yongsok Seo

AbstractWe have developed new flexible dye-sensitized solar cells (DSSCs) comprising organic dye (JH-1), cobalt redox electrolyte and hierarchically structured TiO2 (HS-TiO2) photoelectrode prepared using an electrostatic spray method. The performance of JH-1 sensitized flexible DSSC with a cobalt redox electrolyte was compared with those of N719-based DSSC and DSSC with I-/ I3- redox electrolyte. As a result, JH-1 sensitized flexible DSSC with [Co(Ⅲ/Ⅱ)(bpy-pz)3](PF6)3/2 redox system exhibited a high photocurrent density of 9.17 mA cm-2, an open circuit voltage of 0.953 V, a fill factor of 0.70, and a power conversion efficiency of 6.12% under 1 sun illumination (100 mW cm-2). The incident photon-to-current conversion efficiency was measured to explain the photocurrent generation difference by different dyes and electrolytes. The electron recombination lifetime of cells was measured by intensity-modulated photovoltage spectroscopy. Mass transport in DSSCs employing cobalt redox electrolytes was also investigated by the photocurrent transient measurements and electrochemical impedance spectroscopy (EIS) analysis.


2009 ◽  
Vol 02 (01) ◽  
pp. 27-31 ◽  
Author(s):  
XIANG-DONG GAO ◽  
WEI GAO ◽  
XIAO-DONG YAN ◽  
FU-WEI ZHUGE ◽  
JI-MING BIAN ◽  
...  

Micron-sized ZnO disks with nanosized pores were synthesized by decomposing the solution-grown layered zinc compound ZnCl 2 · [ Zn ( OH )2]4 · H 2 O ( ZCOH ) at 500°C. ZnO – TiO 2 hybrid film electrodes were prepared by the doctor-blade method, adding ZnO disk powder to the TiO 2 slurry. The crystallinity, microstructure and optical properties of the ZCOH , ZnO nanoporous disk, and the resulting hybrid films, were investigated. Electrochemical impedance spectroscopy and the photocurrent density–voltage curve were employed to characterize the interfacial electron-transporting properties and photoelectrochemical performance of dye-sensitized solar cells (DSCs) using the ZnO – TiO 2 hybrid electrode. Results indicated that the incorporation of a small amount of ZnO disks into the TiO 2 film (less than 1%) can roughen the surface structure, reduce the film thickness, enhance the light scattering in the visible and infrared bands, and increase the interfacial charge transport rate. Hybrid cells showed efficiency improvements of 145% and 109% with the concentrations of ZnO of 0.5% and 1% in the hybrid film respectively, compared with the traditional TiO 2 cell, with a significant increase in the short-currency density and the fill factor. Although the 2.7% efficiency (J sc = 4.0 mA ° cm -2; Voc = 0.74 was not high with the 0.5% ZnO disk incorporated, this work highlighted the potential improvement that novel ZnO nanostructures in hybrid DSCs can achieve.


2018 ◽  
Vol 382 ◽  
pp. 369-373
Author(s):  
Usana Mahanitipong ◽  
Preeyapat Prompan ◽  
Rukkiat Jitchati

The four thiocyanate free ruthenium(II) complexes; [Ru(N^N)2(C^N)]PF6were synthesized and characterized for dye sensitized solar cells (DSSCs). The results showed that the broad absorptions covered the visible region from metal to ligand charge transfer (MLCT) were obtained with the main peaks at 560, 490 and 400 nm. The materials were studied DSSC performance under standard AM 1.5. Compound PP1 showed the power conversion efficiency (PCE) at 3.10%, with a short-circuit photocurrent density (Jsc) of 7.99 mA cm-2, an open-circuit photovoltage (Voc) of 563 mV and a high fill factor (ff) of 0.690.


Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4181 ◽  
Author(s):  
Mariia Karpacheva ◽  
Vanessa Wyss ◽  
Catherine E. Housecroft ◽  
Edwin C. Constable

By systematic tuning of the components of the electrolyte, the performances of dye-sensitized solar cells (DSCs) with an N-heterocyclic carbene iron(II) dye have been significantly improved. The beneficial effects of an increased Li+ ion concentration in the electrolyte lead to photoconversion efficiencies (PCEs) up to 0.66% for fully masked cells (representing 11.8% relative to 100% set for N719) and an external quantum efficiency maximum (EQEmax) up to approximately 25% due to an increased short-circuit current density (JSC). A study of the effects of varying the length of the alkyl chain in 1-alkyl-3-methylimidazolium iodide ionic liquids (ILs) shows that a longer chain results in an increase in JSC with an overall efficiency up to 0.61% (10.9% relative to N719 set at 100%) on going from n-methyl to n-butyl chain, although an n-hexyl chain leads to no further gain in PCE. The results of electrochemical impedance spectroscopy (EIS) support the trends in JSC and open-circuit voltage (VOC) parameters. A change in the counterion from I− to [BF4]− for 1-propyl-3-methylimidazolium iodide ionic liquid leads to DSCs with a remarkably high JSC value for an N-heterocyclic carbene iron(II) dye of 4.90 mA cm−2, but a low VOC of 244 mV. Our investigations have shown that an increased concentration of Li+ in combination with an optimized alkyl chain length in the 1-alkyl-3-methylimidazolium iodide IL in the electrolyte leads to iron(II)-sensitized DSC performances comparable with those of containing some copper(I)-based dyes.


2021 ◽  
Author(s):  
S. Revathi ◽  
A Pricilla Jeyakumari

Abstract Currently, the TiO2/CdS photoanodes based dye sensitized solar cells (DSSCs) have shown extraordinary developments in the photo conversion efficiency. In this report, pristine TiO2, CdS and various molar ratios of TiO2/CdS photoanodes were prepared by one step microwave irradiation route and followed by doctor blade method. The sheet like morphology of the TiO2 and CdS nanoparticles were clearly evident from the SEM and TEM images. A significant reduction band gap with enhanced light absorption and rapid prevention of electron hole pair was explored by UV-DRS and PL studies. The photocurrent density-voltage (J-V) and electrochemical impedance (EIS) characteristics were analyzed for assembled solar cell. The photo-conversion efficiency of 12.8% was obtained with the configuration TiO2/CdS (200 mg) that represent a 2.5 fold increment compared to bare TiO2 (5.33%) as well as commercial Pt (6.11%). The experimental results are discussed.


2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Joe Otsuki ◽  
Yusho Takaguchi ◽  
Daichi Takahashi ◽  
Palanisamy Kalimuthu ◽  
Surya Prakash Singh ◽  
...  

We have prepared a novel piperidine-donor-substituted perylene sensitizer, PK0002, and studied the photovoltaic performance in dye-sensitized solar cells (DSSCs). Physical properties and photovoltaic performance of this new perylene derivative PK0002 are reported and compared with those of unsubstituted perylene sensitizer, PK0003. PK0002, when anchored to nanocrystalline TiO2 films, achieves very efficient sensitization across the whole visible range extending up to 800 nm. The incident photon-to-current conversion efficiency (IPCE) spectrum was consistent with the absorption spectrum and resulted in a high short-circuit photocurrent density (Jsc) of 8.8 mA cm-2. PK0002 showed higher IPCE values than PK0003 in the 520–800 nm region. Under standard AM 1.5 irradiation (100 mW cm-2) and using an electrolyte consisting of 0.6 M dimethylpropyl-imidazolium iodide, 0.05 M I2, 0.1 M LiI, and 0.5 M tert-butylpyridine in acetonitrile, a solar cell containing sensitizer PK0002 yielded a short-circuit photocurrent density of 7.7 mA cm-2, an open-circuit photovoltage of 0.57 V, and a fill factor of 0.70, corresponding to an overall conversion efficiency of 3.1%.


Crystals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 389 ◽  
Author(s):  
Y. Klein ◽  
Nathalie Marinakis ◽  
Edwin Constable ◽  
Catherine Housecroft

We report the synthesis and characterization of the first example of an organic dye, PP1, for p-type dye-sensitized solar cells (DSCs) bearing a phosphonic acid anchoring group. PP1 is structurally related to the benchmarking dye, P1, which possesses a carboxylic acid anchor. The solution absorption spectra of PP1 and P1 are similar (PP1 has λmax = 478 nm and εmax = 62,800 dm3 mol−1 cm−1), as are the solid-state absorption spectra of the dyes adsorbed on FTO/NiO electrodes. p-Type DSCs with NiO as semiconductor and sensitized with P1 or PP1 perform comparably. For PP1, short-circuit current densities (JSC) and open-circuit voltages (VOC) for five DSCs lie between 1.11 and 1.45 mA cm−2, and 119 and 143 mV, respectively, compared to ranges of 1.55–1.80 mA cm−2 and 117–130 mV for P1. Photoconversion efficiencies with PP1 are in the range 0.054–0.069%, compared to 0.065–0.079% for P1. Electrochemical impedance spectroscopy, open-circuit photovoltage decay and intensity-modulated photocurrent spectroscopy have been used to compare DSCs with P1 and PP1 in detail.


2014 ◽  
Vol 07 (04) ◽  
pp. 1450039 ◽  
Author(s):  
Liqing Zhang ◽  
Shuai Zhou ◽  
Fengshi Cai ◽  
Zhihao Yuan

ZnO / TiO 2 composite films composed of a ZnO nanoflowers overlayer and a ZnO / TiO 2 composite particulate underlayer were fabricated by a simple hydrothermal process. The as-prepared films were characterized by scanning electron microscopy, transmission electron microscopy (TEM) and diffused reflectance spectroscopy. The performance of dye-sensitized solar cells (DSCs) was investigated by photocurrent–voltage measurements, incident photon-to-current conversion efficiency (IPCE) and electrochemical impedance spectroscopy. It was found that the ZnO / TiO 2 composite film prepared with a 60 min growth time exhibited higher reflectivity than that of pure TiO 2 film due to the effective light-scattering of ZnO nanoflowers, resulting in increased J sc . In the meantime, the open-circuit potential of the device were enhanced from 698 to 826 mV due to the formation of an energy barrier by ZnO at TiO 2/electrolyte interface, resulting in a 52% improvement in the power conversion efficiency from 4.64 to 7.06%.


2011 ◽  
Vol 383-390 ◽  
pp. 5510-5515
Author(s):  
Tien Tsan Hung

Novel phthalocyanine derivative and azo derivative have been synthesized as photosensitizers for the dye-sensitized solar cells (DSSCs). We used sol-gel method to prepare the titanium oxide (TiO2) membrane electrode of the DSSCs. The crystalline phase and surface morphology of TiO2 were characterized by using X-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM) to investigate the effects of processing parameters on the films characteristic, microstructure and thickness. The performance of DSSCs was characterized by using electrochemical impedance spectroscopy (EIS) and current-voltage curve analysis. The sensitizing properties of phthalocyanine derivative, azo derivative and mixed dyes were studied, and it was found that the cell consisted of mixed dyes generated the highest power conversion efficiency () of 2.3 %, short circuit photocurrent density (Jsc) of 13.6 mA cm-2, open circuit photovoltage (Voc) of 0.46 V and fill factor (FF) of 0.37 under simulated AM 1.5 irradiation (100 mW cm-2) with a active area of 0.25 cm2.


2010 ◽  
Vol 132 (2) ◽  
Author(s):  
Chaehyeon Lee ◽  
Weekyung Kang ◽  
Min Jae Ko ◽  
Kyoungkon Kim ◽  
Nam-Gyu Park

Photo-electrochemical properties of dye-sensitized solar cells (DSSCs) were investigated by changing the gap between working and counter electrodes. The open-circuit voltage (VOC) of DSSCs was significantly increased from 616 mV to 776 mV by about 26% with 1-methyl-3-butyl imidazolium iodide (BMII) based electrolyte and from 428 mV to 513 mV by 20% with lithium iodide (LiI) based electrolyte as the cell gap increased from 16 μm to 224 μm. From the electrochemical impedance spectroscopy, it was found that the resistance of the electrolyte was increased as the cell gap widened. This resulted in the reduction in the dark current associated with the VOC enhancement. The transient photovoltage spectroscopic measurement confirmed that the time constant for charge recombination between TiO2 and electrolyte became slower as the cell gap of the DSSC with LiI electrolyte increased, which could be an additional reason for the VOC enhancement. The optimal cell gap was determined to be around 31.3 μm for the BMII electrolyte system, and around 75.5 μm for the LiI electrolyte system in terms of the energy-conversion efficiency.


Sign in / Sign up

Export Citation Format

Share Document