Photoanodes For Dye-sensitized Solar Cells Research Articles

Efficient flexible dye-sensitized solar cells from rear illumination based on different morphologies of titanium dioxide photoanode

The TiO2 with nanoparticles (NPs), nanowires (NWs), nanorods (NRs) and nanotubes (NTs) structures were prepared by using a in-situ hydrothermal technique, and then proposed as a photoanode for flexible dye-sensitized solar cell (FDSSC). The influences of the morphology of TiO2 on the photovoltaic performances of FDSSCs were investigated. Under rear illumination of 100 mW·cm−2, the power conversion efficiencies of FDSSCs achieved 6.96%, 7.36%, 7.65%, and 7.83% with the TiO2 photoanodes of NPs, NWs, NRs, and NTs and PEDOT counter electrode. The FDSSCs based on TiO2 NRs and NTs photoanodes have higher short circuit current densities and power conversion efficiencies than that of the others. The enhanced power conversion efficiency is responsible for their nanotubes and rod-shaped ordered structures, which are more beneficial to transmission of electron and hole in semiconductor compared to the TiO2 nanoparticles and nanowires disordered structure.

Improving charge transfer properties and solar cell performance by In-doped TiO2 as an efficient photoanode for dye-sensitized solar cells (DSSCs)

Dye-sensitized-solar cells (DSSCs) are of great interest as cost-effective and green energy producers. The vastly explored photoanodes are one of the most significant parts of DSSC and still play a crucial role. We employed the fast and facile sol-gel technique to synthesize and dope TiO2 mesoporous structure with indium atoms. Although In doping in the TiO2 structure has been used previously, there have been few research on its application as photoanode in DSSCs. We investigated TiO2:In as an appropriate candidate for photoanode in DSSC and evaluated its charge transfer and optical, structural, and electrochemical properties. Mott-Schottky results show that indium doping can increase the carrier concentration up to 1.1 × 1017 cm−3 and elevate the conductivity as well as charge transfer properties. The optical and structural properties were investigated by PL, Raman, and UV–visible methods, and the results showed that TiO2:In has suppressed recombination in its structure. Also, In-doping improves the electrochemical properties of the photoanodes. The EIS results establish that In corporation can reduce the charge transfer resistance to 33 Ω cm2. The champion TiO2:In-based DSSC shows an 8.62 % efficiency, which indicates a 55 % improvement compared to the non-doped TiO2.

Utilizing the lignocellulosic fibers from Pineapple Crown Leaves extract for enhancing TiO2 interfacial bonding in dye-sensitized solar cell photoanodes

AbstractThe crown leaves of pineapple possess a wealth of smooth and glossy silk medium-length fibers, primarily composed of cellulose and lignin, accompanied by constituents such as fats, waxes, pectin, uronic acid, anhydride, pentosan, color pigments, and inorganic substances. These fibers exhibit an anisotropic nature and are characterized by hydrogen bonding interactions, rendering them effective in conjunction with semiconductor oxide (TiO2) through their cellulosic fibrils. The dye extracted from Pineapple Crown Leaves (PCL) using ethanol was subjected to FTIR and UV–visible spectroscopy. The FTIR analysis revealed absorption peaks at 3268 cm−1 and 2922 cm−1, confirming the presence of –OH and –CH stretching attributed to the fibrils within the dye. UV–visible spectroscopy further demonstrated absorption within the visible region of the electromagnetic spectrum. Additionally, a photoluminescence study of the dye showcased emission within the visible range of the electromagnetic spectrum. Subsequently, a solar cell incorporating this dye underwent JV characterization, yielding an efficiency of 1.0034%, along with fill factor, open-circuit voltage, and short-circuit current density values of 0.40644, 0.7058 V, and 3.4906 mA/cm2, respectively. To gain deeper insights and facilitate optimization for large-scale installations, a simulation model utilizing PC1D was proposed to explore the influential parameters of the Dye-sensitized solar cell (DSSC).

TiO2-bismuth screen printing ink for flexible low temperature dye sensitized solar cells

Flexible dye sensitized solar cells (DSSCs) possess multiple advantages with wide application and good commercialisation potential. However, the low conversion efficiency of the technology from poor charge transfer and interparticle contact has limited their utilisation. Thus, the research aims to enhance the performance of flexible plastic-based titanium dioxide (TiO2) film via the formation of TiO2-bismuth (Bi) ink for screen-printing of DSSC photoanode film. The implementation of Bi nanoparticles as sintering aid has managed to improve the interparticle contact in the photoanode film with neck formation at the TiO2-Bi interface. This phenomenon has also led to the lowering of resistance values by 57 - 65% with charge transfer resistance of 11.72 kΩ.cm2 and series resistance of 38.28 kΩ.cm2 for the TiO2-Bi photoanode. The recombination reactions were also reduced with longer electron lifetime of 0.0036 ms and enhanced charge transfer. The research has managed to prepare TiO2-Bi ink that would be suitable for the fabrication of flexible DSSC photoanode film via screen printing. Hence, the outcome of the research could potentially lead to the development of highly efficient flexible low temperature DSSC and enhance their commercialisation potential.

Investigating the effect of ZrO2 nanofibers in ZnO-based photoanodes to increase dye-sensitized solar cells (DSSC) efficiency: Inspecting the porosity and charge transfer properties in ZnO/ZrO2 nanocomposite photoanode

This study is aimed to improve the performance of zinc oxide (ZnO) photoanodes in dye-sensitized solar cells (DSSCs) by exploiting the superior charge transport properties in electro-spun zirconium dioxide (ZrO2) nanofibers in ZnO/ZrO2 nanocomposite photoanodes. The fabricated photoanodes were analyzed by a variety of analyses. The XRD results show that photoanodes are a mixture of two different phases of ZnO and ZrO2 without any additional impurity phase. FESEM images and BET analysis show changes in porosity and effective surface area in the synthesized photoanodes. UV–Vis analysis confirms this conclusion by measuring adsorbed dye molecules on the photoanode surface. In addition, using the photoanodes, DSSCs are prepared for which J-V characterization results show an increase in efficiency from 1.68 to 3.31 %. The addition of ZrO2 nanofiber to the ZnO network increases the porosity and effective surface area and makes it possible to control the dye-loading as well as electrolyte species transport. Furthermore, the results of EIS analysis show that the charge transport in the ZnO/ZrO2 network is carried out more efficiently compared to the bare ZnO photoanode. Although, increasing ZrO2 nanofibers to a certain level can help improve the efficiency, it tends to reduce the efficiency with ZrO2/ZnO ratios of over 10 %.

Effect of zinc oxide incorporation of poly (aniline)-titanium dioxide ternary nanocrystalline photo-anode for dye-sensitized solar cell applications

In this work, we have developed optically transparent zinc oxide nanoparticles doped with highly efficient of poly (aniline)-titanium dioxide (PANI/TiO2/ZnO) ternary composites were prepared by simple chemical oxidative polymerization method and its used as photo-anode for dye-sensitized solar cell (DSSC) applications. The as prepared PANI/TiO2/ZnO characterized by the various techniques such as FT-IR, XRD, HR-TEM, SAED, FE-SEM, AFM, and UV–Visible analysis. Morphological analysis was observed in the surface morphology of ZnO doped PANI/TiO2 in crystalline nature. The topographical AFM images were also observed in crystalline nature. Tauc plot analysis were examined the optical band-gap energy (2.95 eV) of PANI/TiO2/ZnO. The DSSCs assembled and as prepared PANI/TiO2, PANI/ZnO, TiO2/ZnO, PANI/TiO2/ZnO were used as photo-anode, 1-hexyl-3-methylimidazolium iodide containing the iodide/triiodide redox mediator used as the electrolyte, platinum paste used as a counter electrode. Among the devices, PANI/TiO2/ZnO photo-anode gives 8.31% efficiency.

An overview of bi-layered niobium pentoxide (Nb2O5)-based photoanodes for dye-sensitized solar cells

An overview of bi-layered niobium pentoxide (Nb2O5)-based photoanodes for dye-sensitized solar cells

Facile synthesis of reduced graphene oxide and graphitic carbon nitride modified titanium dioxide nanospheres for photoanode of dye-sensitized solar cell

Titanium dioxide/reduced graphene oxide nanocomposites (TiO2/rGO NCs) have been broadly utilized as photoanode materials for dye-sensitized solar cell (DSSC). Nevertheless, photoelectric conversion efficiency (PCE) of DSSC is diminished due to recombination of charges takes place between photoanode and electrolyte interface. Herein, we have prepared a triplet structure nanocomposite composed of TiO2 nanospheres, rGO and graphitic carbon nitride (TiO2 NS/rGO/g-C3N4 NC) for photoanode of DSSC. The ternary TiO2 NS/rGO/g-C3N4 NC photoanode has enhanced dye absorption considerably and as a consequence, improved light harvesting efficiency. Besides, the introduction of rGO and g-C3N4 on the TiO2 NS has effectually speeded up the transport of electrons and minimized the recombination of photogenerated charges. Consequently, the DSSC integrated with ternary TiO2 NS/rGO/g-C3N4 NC photoanode has exhibited ∼41 % increment in the PCE of 5.77 % when compared to PCE of the pristine TiO2 NS photoanode (4.10 %). This finding has proposed a simplistic approach to advance photovoltaic performance of the DSSC.

Photocurrent Density Enhancement of DSSC with Existence of ZnO in TiO2 Based Photoanode

<p class="Abstract"><span lang="EN-US">One of the important components of a dye-sensitized solar cell (DSSC) is photoanode which plays a critical role serving as the center of conversion energy. Photoanode consists of transparent conducting substrate, a semiconductor layer, and dyes molecules as sensitizers. Titanium dioxide (TiO<sub>2</sub>) is widely used as a photoanode because it is a mesoporous and stable material despite its high recombination rate. To reduce the recombination rate and improve electron transport, TiO<sub>2</sub> is combined with other materials such as ZnO to form TiO<sub>2</sub>/ZnO composites. ZnO is a good choice because it has higher electron mobility than TiO<sub>2</sub> to inhibit recombination. The synthesis process of TiO<sub>2</sub>/ZnO composites was carried out using the sol-gel method with variations in the weight percentage of ZnO. The TiO<sub>2</sub>/ZnO composite was then applied as a photoanode in DSSC. The J-V measurement results shows that the DSSC with TiO<sub>2</sub>/ZnO 25wt% composite layer as the photoanode produced the highest efficiency of 0.86%. This increase in efficiency was due to an increase in the photo-current of photoanodes that have more ZnO content. The presence of ZnO leads to faster-moving electron transport, therefore reducing recombination and increasing efficiency.</span></p>

Synthesis of Mg-doped TiO2 Using a Hydrothermal Method as Photoanode on Bixin-Sensitized Solar Cell

Titanium dioxide (TiO2) with magnesium (Mg) doping for dye-sensitized solar cell (DSSC) photoanode application has been synthesized. DSSC components used in this study were photosensitizer (bixin), electrolyte (), cathode (platinum), and photoanode (Mg-TiO2). This research aims to determine the characteristics of Mg-doped TiO2 photoanode with variations in dopant concentration based on the results of XRD and DR/UV-Vis analysis, as well as to determine the maximum efficiency conversion energy of DSSC using Mg-doped TiO2 and undoped TiO2 as photoanodes. The synthesis of TiO2 and Mg-TiO2 was carried out using the hydrothermal method with variations in the concentration of Mg dopant of 0, 0.5, 1, and 2% based on the molar ratio. The presenceof 2% of Mg in anatase TiO2 paste decreased the TiO2 band gap from 3.15 to 2.60 eV. Analysis results show that adding Mg dopant decreased the crystal size. Mg dopants on TiO2 could also form new energy levels, which reduced the band gap energy of TiO2. In addition, the increased concentration of Mg dopants also shifted the absorption capacity of TiO2 from the ultra-violet (UV) wavelengths region to the visible light area. The maximum energy conversion efficiency of the DSSCs with Mg-doped TiO2 photoanode of 0.5, 1, and 2% are 0.045; 0.070, and 0.172%, respectively, where these three efficiency values are higher than undoped TiO2 (0.017%). The results proved that the presence of Mg dopants on the TiO2 photoanode can increase the efficiency of DSSC.

Dye-sensitized solar cells with efficiencies exceeding 10% engineered based on La2MnTiO6 double perovskite and MOF-derived Cr2O3/C nanocomposites in bi-layered photoanodes

To improve the photoanode performance of dye-sensitized solar cells (DSSCs), developing double-layered photoanodes have been proposed consisting of La2MnTiO6 + Cr2O3/C nanocomposites in diverse ratios to find the optimal amount. The (x%) La2MnTiO6 + (y%) Cr2O3/C nanocomposites were coated as the overlayer and TiO2 nanoparticles as the underlayer in photoelectrodes. La2MnTiO6, Cr2O3/C, and La2MnTiO6 + Cr2O3/C nanocomposites have been synthesized using sol-gel method, MIL-101(Cr), and hydrothermal method, respectively, and applied as effective light-absorbing photoelectrode layers on the top of TiO2 photoanode in DSSC and compared to TiO2 monolayer film. Numerous analyses and photocurrent density-voltage (J-V) plots were taken to evaluate nanocomposites characteristics. Because of superior light absorbing as well as light-scattering abilities, high amount of dye loading, porous surfaces with high electron transport capacity, and less electron-hole recombination at the 70%La2MnTiO6 + 30%Cr2O3/C film/TiO2/electrolyte interface, the champion cell based on TiO2/20% (70%La2MnTiO6 + 30%Cr2O3/C) photoanode showed a 2.19-fold higher power conversion efficiency (PCE = 9.00%) than the traditional TiO2 monolayer based photoanode (PCE = 4.11%). The amount of the 70%La2MnTiO6 + 30%Cr2O3/C composite loading in the second layer film on the TiO2 layer was also varied in photoanodes. By optimizing the percentage of composite loaded in the second layer, champion device with optimal TiO2/15% (70%La2MnTiO6 + 30%Cr2O3/C) nanocomposite unveiled the largest PCE = 10.07%, enhancing the PCE by about 11.8% and 145% in comparison with TiO2/20% (70%La2MnTiO6 + 30%Cr2O3/C) and monolayer TiO2 photoanodes, respectively.

Emulsion-assisted polyaniline grown on molybdenum diselenide nanoflowers for efficient counter electrode application in dye-sensitized solar cells

ABSTRACT Molybdenum diselenide (MoSe2) is often composed with conducting polymers like polyaniline (PANI) to lower the stacking and increase the active sites for catalysis. The method of polymerization and the concentration of monomer play a significant role in the growth of PANI nanostructures over the MoSe2 surface. Here, MoSe2-PANI nanocomposites have been synthesized with different molar concentrations of the monomer in the emulsion of chloroform and distilled water using ammonium persulfate (APS) as the initiator. The increased surface area of the composite MPAN (1:1) compared to pristine MoSe2, as observed from the FESEM and BET study, is fruitful for counter-electrode application in dye-sensitized solar cells (DSSC). The lower Rct values for the MPAN (1:1) and increased current in cyclic voltammetry further approved the suitability of the MoSe2-PANI as a counter electrocatalyst. The counter electrodes against N719 dye-sensitized TiO2 photoanode in DSSC yielded the best results for MPAN (1:1), generating an efficiency of 6.45%.

Structural, optical and photovoltaic properties of V2O5/ZnO and reduced graphene oxide (rGO)-V2O5/ZnO nanocomposite photoanodes for dye-sensitized solar cells

Structural, optical and photovoltaic properties of V2O5/ZnO and reduced graphene oxide (rGO)-V2O5/ZnO nanocomposite photoanodes for dye-sensitized solar cells

Effects of mesoporous TiO2 with addition of V2O5 and rinsing with various solvents on the properties of dye-sensitized solar cells

Dye-sensitized solar cells (DSSC) have received much attention since they are simple, easily manufactured, inexpensive, and offer reasonable conversion efficiency. Mesoporous TiO2 with the addition of V2O5 nano-particles (0, 0.5, 1.0, 1.5 and 2.0 wt%) as a photoanode in DSSC have been successfully fabricated using a spin-coating method. Titanium tetrachloride (TiCl4) was used to synthesize a thin TiO2 blocking layer to enhance the performance of TiO2 photoanode in DSSC. After annealing treatment at 450 °C, the TiO2 blocking layer showed an amorphous structure. Performance was examined after soaking N719 dye and rinsing with five different solvents (ethanol, isopropanol, acetone, methanol, and diethyl ether). The results show that removing unanchored dye molecules using acetone solution can increase the specific surface area and dye adsorption amount of TiO2, resulting in good Jsc and photovoltaic efficiency. A conversion efficiency of 8.5% was achieved using fluorine doped tin oxide glass, a thin blocking layer, mixing 0.5 wt% V2O5 with mesoporous TiO2 and rinsing with an acetone solution.

Effect of electrospun bilayer titanium oxide–tin oxide nanofibers on the performance of dye-sensitized solar cells

The core–shell nanofibers, which contain titanium oxide (TiO2) and tin oxide (SnO2), are known as electrospun nanofibers that improve the performance of dye-sensitized solar cells by exploring the photoanode. The morphology and microstructure of the electrospun nanofibers are studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X–ray diffraction (XRD). Based on the SEM micrographs, the fibers have a bilayer TiO2–SnO2 core–shell structure with a 70–120 nm diameter. The XRD analysis shows the dominant crystalline phase of the synthesized nanostructures after heat treatment. Finally, the synthesized nanofibers are used to prepare dye-sensitized solar cell photoanodes with thicknesses of 8, 11, 14, and 17 μm, which their performances are investigated. The current–voltage (I–V) curve of the solar cells under the Xenon lamp irradiation is measured and calculated. The optimal solar cell with a photoanode made electrophoretic at 30 V for 8 min shows the best performance. The optimal thickness of the TiO2–SnO2 nanocomposite for this photoanode is 14 μm. The short-circuit current density, open-circuit voltage, and optimal cell efficiency for this sample are 19.35 mA/cm2, 650 mV, and 9.27%, respectively.

Barium titanate perovskite nanoparticles integrated reduced graphene oxide nanocomposite photoanode for high performance dye-sensitized solar cell

Nanocomposites comprised of barium titanate perovskite nanoparticles decorated reduced graphene oxide (BaTiO3-RGO NC) were formed through facile hydrothermal method. X-ray diffractometer profile confirmed crystallite and tetragonal phase of BaTiO3. Identification of D and G bands in Raman investigation and XPS spectra disclosed existence of graphene in the prepared BaTiO3-RGO NC. FE-SEM examination indicates small sized BaTiO3 NPs are obviously decorated on the graphene sheets by strong binding forces between graphene and BaTiO3 NPs. Among graphene of different wt%, BaTiO3-RGO NC with 1.5 wt% showed lowest PL intensity, indicating effective reduction of photogenerated charge carrier recombination. Dye-sensitized solar cell fabricated using BaTiO3-RGO NC photoanode having 1.5 wt% graphene displays high efficiency of 4.93% associated with high photocurrent density.

Green Synthesis of Pristine and Ag-Doped TiO2 and Investigation of Their Performance as Photoanodes in Dye-Sensitized Solar Cells.

Dye-sensitized solar cells (DSSCs) have emerged as a potential candidate for third-generation thin film solar energy conversion systems because of their outstanding optoelectronic properties, cost-effectiveness, environmental friendliness, and easy manufacturing process. The electron transport layer is one of the most essential components in DSSCs since it plays a crucial role in the device's greatest performance. Silver ions as a dopant have drawn attention in DSSC device applications because of their stability under ambient conditions, decreased charge recombination, increased efficient charge transfer, and optical, structural, and electrochemical properties. Because of these concepts, herein, we report the synthesis of pristine TiO2 using a novel green modified solvothermal simplistic method. Additionally, the prepared semiconductor nanomaterials, Ag-doped TiO2 with percentages of 1, 2, 3, and 4%, were used as photoanodes to enhance the device's performance. The obtained nanomaterials were characterized using XRD, FTIR, FE-SEM, EDS, and UV-vis techniques. The average crystallite size for pristine TiO2 and Ag-doped TiO2 with percentages of 1, 2, 3, and 4% was found to be 13 nm by using the highest intensity peaks in the XRD spectra. The Ag-doped TiO2 nanomaterials exhibited excellent photovoltaic activity as compared to pristine TiO2. The incorporation of Ag could assist in successful charge transport and minimize the charge recombination process. The DSSCs showed a Jsc of 8.336 mA/cm2, a Voc of 698 mV, and an FF of 0.422 with a power conversion efficiency (PCE) of 2.45% at a Ag concentration of 4% under illumination of 100 mW/cm2 power with N719 dye, indicating an important improvement when compared to 2% Ag-doped (PCE of 0.97%) and pristine TiO2 (PCE of 0.62%).

Synthesis of TiO<sub>2</sub> Nanofiber as Photoanode of Dye Sensitized Solar Cells (DSSC)

Recently, dye sensitized solar cell (DSSC) are considered to replace the previous generation of solar cells. DSSC uses an organic dye to absorb light and convert it to electricity. One-dimensional morphological structure of photoanode that provides a straight pathway for electron transport can improve the efficiency of DSSC. TiO2 nanofibers is one-dimensional structure of oxide semiconductor material commonly used as photoanode in DSSC. A simple method to synthesis continuous nanofiber is electrospinning method that use the influence of electrostatic forces. The nanofiber’s diameter that produced by electrospinning method depends on several parameters, one of which is the applied voltage. This study reports the synthesis of TiO2 nanofibers with varying the applied voltages from 10 kV to 14 kV and their performance as photoanode in DSSC. TiO2 nanofibers were electrospun directly onto a TiO2-coated fluorine tin oxide (FTO) substrate from a mixture of titanium (IV) propoxide (TTIP), triton X-100, acetic acid, poly (vinyl) acetate (PVAc) that were dissolved in dimethyl formamide (DMF). TiO2 nanofiber photoanodes were then immersed in ruthenium (II) dye, stacked with a counter electrode, and finally the electrolyte was injected between them. Based on the SEM results, we found that the beads disappeared with increasing applied voltage. The XRD pattern of TiO2 nanofibers indicates the presence of the anatase phase. Based on the photocurrent-voltage characteristic, TiO2 nanofibers produced by applied voltage of 14 kV shows the highest efficiency of 1.11% with JSC 4.78 mA/cm2, VOC 0.74 Volt and fill factor (FF) of 31.37%.

Performance Improvement of Dye-Sensitized Solar Cells Using a Combination of TiO<sub>2</sub> and ZnO as Photoanodes

TiO2 are usually used as photoanode to get high-performance dye-sensitized solar cells (DSSCs). TiO2 has good chemical stability, but still has poor electron mobility so that the DSSC efficiency is low. An alternative semiconductor metal-oxides such as ZnO currently are being explored due to ease of processing, higher electron mobility, interface band energetics, and can be utilized as photoanode also, but the chemical stability is low. Based on these facts, by combining the advantages of TiO2 and ZnO, the TiO2:ZnO composite can be an ideal material as a photoanode in DSSC. In this study, composite of TiO2:ZnO was synthesized using sol-gel method with ratio of TiO2 to ZnO were varied from 80:20, 60:40, 50:50, 40:60, and 20:80 in atomic percent. DSSCs were fabricated by coating the photoanode using screen-printing technique on a FTO-glass substrate. Composite of TiO2:ZnO photoanodes were then sensitized in a solution of N719 dye for several hours. Finally, the DSSCs were assembled and the power conversion efficiency was measured using an I–V measurement system. The highest power conversion efficiency of 2.30% was obtained from the cell fabricated with TiO2:ZnO (50:50) photoanode. This result indicated that the balanced composition allowed to increase Jsc along with reducing recombination process and retaining high dye-loading capability.

Application of Carbon Nanosphere Templates for Preparation of Inverse Opal Photonic Crystals in Dye‐Sensitized Solar Cells

Carbon nanospheres are successfully synthesized with a particle size of about 140 nm using a two‐step hydrothermal method and used the carbon nanospheres as the deposition template material on the surface of P25(TiO2) by means of vertical deposition method. The antiopaline TiO2 photonic crystal (PC) structure is further prepared via immersed carbon nanospheres in TiO2 precursor solution, and the antiopal PC is used as the scattering layer of the photoanode of dye‐sensitized solar cell (DSSCs). As a comparison, the antiopal PC reflective layer is also prepared on the photoanode of DSSCs using polystyrene nanospheres as the template material. The photoanodes with those PC scattering layers prepared with different template materials are fabricated into complete DSSCs. The final photoelectric conversion efficiency of the DSSCs prepared with carbon nanospheres as the template material reaches 7.02%, which is comparable to the cells prepared with polystyrene nanospheres as the template material. The efficiency of the cell with the scattering layer is increased by about 16% compared with that of the normal DSSC based on P25.