Electrodes For Dye-sensitized Solar Cells Research Articles

Characterization of PAN-TiO2 Nanofiber Mats and their Application as Front Electrodes for Dye-sensitized Solar Cells

In the context of the energy transition to renewables, the spotlight is on large systems connected to the power grid, but this also offers room for smaller, more specialized applications. Photovoltaics, in particular, offer the possibility of the self-sufficient supply of smaller electrical appliances on smaller scales. The idea of making previously unused surfaces usable is by no means new, and textiles such as backpacks, tent tarpaulins and other covers are particularly suitable for this purpose. In order to create a non-toxic and easily recyclable product, dye-sensitized solar cells (DSSC), which can be manufactured through electrospinning with a textile feel, are an attractive option here. Therefore, this paper investigates a needle electrospun nanofiber mat, whose spin solution contains polyacrylonitrile (PAN) dissolved in dimethyl sulfoxide (DMSO) as well es TiO2 nanoparticles. In addition to characterization, the nanofiber mat was dyed in a solution containing anthocyanins to later serve as a front electrode for a dye-sensitized solar cell. Although of lower efficiency, the DSSC provides stable results over two months of measurement.

Synthesis of lignite-based Ni/C composite with low-medium temperature pyrolysis method as an efficient Pt-free counter electrode for dye-sensitized solar cells

In order to obtain inexpensive Pt-free counter electrode materials for dye-sensitized solar cells and expand the application fields of low-rank coal, lignite-based Ni/C composite was prepared by low-medium temperature pyrolysis method using Huolinhe lignite as raw materials. The structure and chemical components of as-synthesized lignite-based Ni/C composite was characterized by XRD, FT-IR, TG, Raman, SEM, TEM, and XPS, and the electrocatalytic activity of lignite-based Ni/C composite counter electrode was investigated by cyclic voltammetric curve, electrochemical impedance spectrum, and Tafel polarization curve. It is found that the electrocatalytic activity of the lignite was improved after low-medium temperature pyrolysis and composited with Ni species to form lignite-based Ni/C composite, which helps to catalyze the reduction of electrolyte and thus improve the photoelectric conversion efficiency of the solar cells. The photoelectric conversion efficiency (η) of the dye-sensitized solar cells based on the lignite-based Ni/C composite counter electrode was 3.42% (Jsc = 11.49 mA cm−2, Voc = 0.75 V, FF = 0.40) significantly higher than that of the lignite counter electrode (η = 0.20%, Jsc = 3.16 mA cm−2, Voc = 0.72 V, FF = 0.09). This indicates that low-medium temperature pyrolysis and composition with Ni are an effective method to improve the photovoltaic performance of lignite-based counter electrode materials.Graphical abstractThe lignite-based Ni/C composite was synthesized and applied in counter electrode for DSSCs.

Eco-friendly direct-current pulsed electropolymerization of polyaniline nanofibers on synthetic graphite substrate for counter electrode in dye-sensitized solar cells

ABSTRACT This paper reports the study of the effect of varying duty cycles on the synthesis of PANI by pulsed electropolymerization method to the performance of PANI as a counter electrode in DSSC. The deposited PANI is in emeraldine salt form, confirmed by FTIR-ATR and Raman spectroscopy. SEM analysis observed that all PANIs has nanofiber morphology. PANI with a 10% duty cycle provides the smallest average diameters and lowest film thickness (11.56 μm), lowest RCT (59.00 Ω), lowest RS (40.06 Ω), highest VOC (0.688 V), and highest JSC (9.066 mA cm−2) that lead to the highest performance (η = 2.402%).

Facile synthesis of cobalt sulfide/carbon nanotube composites as a low-cost Pt-free counter electrode for dye-sensitized solar cells (DSSCs)

In this work, a nanocomposite of CoS2 with multiwalled carbon nanotubes (MWCNTs) has been prepared using simple hydrothermal technique. Further, CoS2/CNT composite was charecterized by X-ray diffraction (XRD), Scanning electron microscope (SEM), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and N2 adsorption-desorption to study the crystallinity, surface morphology chemical composition with chemical states and textural properties, respectively. The cyclic voltammetric tests recorded an enhanced electrocatalytic activity when the CoS2 was deposited onto the surface of the MWCNTs. Additionally, consecutive cyclic voltammetric tests demonstrated that the CE possessed excellent electrochemical stability. Thus, the DSSC assembled with CoS2/MWCNT CE showed an enhanced photovoltaic conversion efficiency of 8.85 ± 0.03 % (compared to 1.84 ± 0.03 % for DSSCs with MWCNT CE or 2.87 ± 0.04 % for CoS2 CE alone) under full sunlight illumination (100 mW cm−2, AM1.5 G) due to the superior electrocatalytic activity of the out-shell CoS2 material and highly specific surface of the MWCNTs. Therefore, the CoS2/MWCNT composite can be considered as a promising alternative CE for use in low-cost DSSCs.

Tungsten Phosphide Microsheets In‐Situ Grown on Carbon Fiber as Counter Electrode Catalyst for Efficient Dye‐Sensitized Solar Cells

AbstractThe development of low‐cost, green, and pollution‐free counter electrode materials with high catalytic activity plays a critical role in improving the photovoltaic performance of dye‐sensitized solar cells (DSSCs). In recent years, transition metal phosphides have been widely used in DSSCs due to their outstanding catalytic activity and stability. Herein, a novel binary phosphide is immobilized on carbon paper (CP) by a two‐step strategy. This strategy involves the preparation of WO3 precursor by the hydrothermal method, and synthesis of tungsten phosphide (WP) with the vapor deposition method, which finally leads to the uniform dispersion of WP on carbon paper. The acquired WP/CP counter electrode demonstrates high electrical conductivity and prefect catalytic ability for reducing triiodide, and the DSSCs assembled with WP/CP counter electrode achieve a high‐power conversion efficiency of 10.29%, which is superior to that of the Pt‐based (7.34%). These findings illustrate that the WP microsheets in‐situ grown on carbon paper are a potential candidate to replace Pt as an economical and efficient counter electrode for DSSCs.

The surfactants mediated electropolymerized poly(aniline) (PANI)-reduced graphene oxide (rGO) composite counter electrode for dye-sensitized solar cell

In this work, poly(aniline) (PANI)–reduced graphene Oxide (rGO) low-cost nanocomposite used for counter electrode (CE) in dye-sensitized solar cells (DSSCs) for the replacement of the high-cost platinum (Pt) CE. The nanocomposite CEs were prepared with three different types of structural determine agents (cationic, non-ionic and anionic namely CTAB, Triton-X100, SDS) in aqueous medium and characterized by HR-SEM & TEM, XRD pattern analysis, FT-IR and Raman spectral studies. Electrochemical impedance spectroscopy (EIS) studies were used to determine the PANI-rGO-anionic surfactant in lower charge transfer resistance compared with, PANI, rGO and other type surfactants used in the preparation of CEs. DSSC assembled with a N719 dye sensitized TiO2 photo-anode, Poly(ethylene oxide) (PEO), iodide/triiodide redox couple containing electrolyte and PANI-rGO-anionic surfactant CE showed a sunlight-into-electrical energy conversion efficiency of 7.60%, which is higher than that of DSSC fabricated with pure Pt (6.40%), PANI (4.81%), rGO (4.30%) and PANI-rGO-CTAB (6.26%) and PANI-rGO-Triton X 100 (5.72%).

Hierarchical carbon nanofibers/carbon nanotubes/NiCo nanocomposites as novel highly effective counter electrode for dye-sensitized solar cells: A structure-electrocatalytic activity relationship study

Herein, we propose novel, highly effective Pt-free counter electrode (CE) material for dye-sensitized solar cells (DSSC) based on the hierarchical carbon nanofibers/carbon nanotubes/NiCo (eCNF/CNT/NiCoNP) ternary nanocomposites. The materials were obtained by combining the electrospinning technique and CCVD synthesis of carbon nanotubes directly on the surface of eCNF. By using various conditions of the CNT growth, it was possible to obtain series of nanocomposites differing with their morphology, surface chemistry, and structural ordering. The conducted studies unraveled significant correlations between the disordering of the nanocomposites, and their electrocatalytic activity towards reduction of I3−. The investigation methods included i.a. SEM, TEM, XPS, UPS, EDS, XRD, SAED, CV, EIS and J-V characterizations. The counter electrodes based on the nanocomposite synthetized at the lowest CCVD temperature of 700 °C exhibited remarkable catalytical activity as evidenced by very low charge transfer resistance of 0.93 Ω cm2. Based on the obtained data, we propose new, alternative interpretation of the additional minor arc appearing at the high-frequency region of EIS Nyquist spectra of carbon based-CE. The DSSC with eCNF/CNT/NiCoNP-electrodes were characterized by efficiencies up to 7.08% (avg. η = 6.95%), which was higher than for Pt-based devices (avg. η = 6.80%), thus demonstrating excellent performance of prepared CE. Our results confirm that the eCNF/CNT/NiCoNP nanocomposite material is a promising low-cost CE alternative for DSSC.

Nanoflower-like P-doped Nickel Oxide as a Catalytic Counter Electrode for Dye-Sensitized Solar Cells.

Flower-like phosphorus-doped nickel oxide (P-NiO) is proposed as a counter electrode (CE) for dye-sensitized solar cells (DSSCs). The flower-like nickel oxide essentially serves as the matrix for the CE, which is expected to promote a two-dimensional electron transport pathway. The phosphorus is intended to improve the catalytic ability by creating more active sites in the NiO for the catalysis of triiodide ions (I3-) to iodide ions (I-) on the surface of the CE. The P-NiO is controlled by a sequencing of precursor concentration, which allows the P-NiO to possess different features. The debris aggregation occurs in the P-NiO-1, while the P-NiO-0.75 leads to the incomplete flower-like nanosheets. The complete flower-like morphology can be observed in the P-NiO-0.5, P-NiO-0.25 and P-NiO-0.1 catalytic electrodes. The DSSC with the P-NiO-0.5 CE achieves a power conversion efficiency (η) of 9.05%, which is better than that of the DSSC using a Pt CE (η = 8.51%); it also performs better than that with the Pt CE, even under rear illumination and dim light conditions. The results indicate the promising potential of the P-NiO CE to replace the expensive Pt CE.

Retraction Note: Bi5FeTi3O nanotubes incorporated with g-C3N4 nanosheets as novel Pt-free counter electrode in dye-sensitized solar cells

Retraction Note: Bi5FeTi3O nanotubes incorporated with g-C3N4 nanosheets as novel Pt-free counter electrode in dye-sensitized solar cells

Layer assembled polyaniline and CuWO4 film as Pt-free efficient counter electrodes of dye-sensitized solar cells

The development of transition metal compounds (TMCs) and conductive polymers composite catalysts substitute for the traditional scarce Pt-based catalysts of counter electrodes (CEs) has been recognized as one of the distinguishing paths to enhance power conversion efficiency (PCE) and decrease manufacturing costs of dye-sensitized solar cells (DSSCs). At present, various thin film preparations have been developed and applied to prepare assortment CEs. Herein, both polyaniline (PANI) and CuWO4 film were prepared, and further to fabricate layer-by-layer composite CEs of CuWO4/PANI, PANI/CuWO4, CuWO4/PANI/CuWO4, PANI/CuWO4/PANI, aiming to promote the charge transfer capability and thus improve catalytic activity. And then, PANI, CuWO4 and four composite layered CEs obtained PCE values of 5.14, 5.64, 5.96, 6.21, 4.96 and 4.24% toward the regeneration of I3−/I− redox couples in the assembled DSSCs, respectively. Particularly, the fascinating performance of the bilayer PANI/CuWO4 CEs inherits the excellent electrical conductivity and the abundant porous structure of PANI skeletons for effective electrolyte diffusion. Meanwhile, the CuWO4 layer was coupled to the layers of PANI by thermal activation annealing treatment to furnish rich inner active sites for the regeneration of I3−/I− couples. Benefit from the synergistic effects of PANI and CuWO4, the as-prepared PANI/CuWO4 CEs manifests the highest PCE of 6.21%, indicating an inspiring strategy by the layered assembly Pt-free CEs with the cost effective and high-performance as an alternative Pt-based catalyst for DSSC.

Tin Sulfide (SnS) Films Deposited by an Electric Field-Assisted Continuous Spray Pyrolysis Technique with Application as Counter Electrodes in Dye-Sensitized Solar Cells.

The deposition of tin sulfide (SnS) nanostructured films using a continuous spray pyrolysis technique is reported with an electric field present at the nozzle for influencing the atomization and the subsequent film deposition. In the absence of the electric field, the X-ray diffraction pattern shows the orthorhombic phase of SnS with a crystallographic preferred orientation along the (040) plane. The application of the electric field results in significant improvement in the morphology and a reduction in surface roughness (28 nm from 37 nm). The direct optical band gap of the films deposited with and without the electric field is estimated to be 1.5 and 1.7 eV, respectively. The photothermal deflection spectroscopy studies show a lower energetic disorder (no Urbach tail), which indicates an annealing effect in the SnS films deposited under the electric field. The improvement in the film properties is reflected in the expected improvement in the power conversion efficiency (PCE) of dye-sensitized solar cells fabricated using the SnS film as a counter electrode. An enhancement of PCE from 2.07% for the film deposited without the electric field to 2.89% for the film deposited with the electric field shows the role of the electric field in the fabrication of improved SnS films.

One-pot hydrothermal in situ growth of In4SnS8@MoS2@CNTs as efficient Pt-free counter electrodes for dye-sensitized solar cells

Developing a synthesis method for large-scale preparation of efficient and economical non noble metal counter electrode (CE) electrocatalytic materials with good catalytic ability and stability is an ideal choice for the commercialization of dye-sensitized solar cells (DSSCs). In this paper, a novel micro-nanostructured composite of CE was prepared by fixing the In4SnS8 and MoS2 on carbon nanotubes (CNTs) and using a one-step hydrothermal strategy. The devices based on the In4SnS8@MoS2@CNTs composite CE performs high power conversion efficiency of 8.72%, far more than that of the device with the control ones (7.57%). The In4SnS8@MoS2 composite were homogeneously distributed on the CNTs surface to form a new In4SnS8@MoS2@CNTs composite network heterojunction. This distinctive porous structure can provide greater contact area and electronic transmission channel to ensure fast charge transport of electrolyte. The prefect electrochemical properties of the In4SnS8@MoS2@CNTs CE for the I−/I3− electrolyte also have been demonstrated by a series of electrochemical tests. As a result, it can be considered that the In4SnS8@MoS2@CNTs will replace the Pt CE and has broad application prospects in DSSCs.

Non-precious transition metal-based counter electrodes for dye-sensitized solar cells

Non-precious transition metal-based counter electrodes for dye-sensitized solar cells

One-step solvothermal method synthesizes petal-like Cu2WSx supported on carbon paper used in dye-sensitized solar cells

Sheet-like transition metal sulfides have promising applications in photocatalysis and energy conversion. This study provides a petal-like Cu2WSx nanosheet structure supported on carbon paper (CP) synthesized by a simple one-step solvothermal method. Cu2WSx microstructures with different morphologies were synthesized by solvothermal vulcanization of thioacetamide (TAA) at different concentrations. The Cu2WSx/CP was used as the counter electrode of DSSCs and compared with the Pt FTO electrode. It was proved that Cu2WSx-7 M/CP had the best electrocatalytic performance and obtained 9.01% photoelectric conversion efficiency. The different sulfide concentration changes the morphology of Cu2WSx and continuously affects the specific surface area and catalytic activity of the material. The better electrochemical performance shows that Cu2WSx/CP is expected to become a substitute for expensive Pt CE materials in dye-sensitized solar cells (DSSCs).

1D ZnO@C@MoS2 nanoarrays as counter electrodes for dye-sensitized solar cells

Herein, 1D [email protected]@MoS2 nanoarrays on conducting glass were fabricated by the successive hydrothermal-dip-coating-sulfurization techniques, acting as an effective counter electrode for the reduction from triiodide to iodide for dye-sensitized solar cells. The power conversion efficiency of 3.61% has been obtained based on 1D composite counter electrodes due to the enhancement of accelerated electron transfer and electrocatalytic activity.

Ni3S2 entrenched MWCNT composite as a low-cost Pt-free counter electrode for dye-sensitized solar cell: Conversion efficiency reached to 9.28%

• A simple and cost effective hydrothermal method was adopted to synthesize ultrafine Ni 3 S 2 /MWCNT hybrid CEs. • Ni 3 S 2 /CNT50 composite counter electrode has the maximum Power Conversion Efficiency (PCE) of 10.2 %. • This could be due to the Enhancing the light absorption property in the visible light region and diminish the recombination process. Engineering the surface structure and constructing a suitable internal conductive network is essential for the electron transfer rate and the active materials utilization efficiency of an electrode A novel porous micro-nanostructure based on nickel disulfide (Ni 3 S 2 ) nanoparticles interconnected with carbon nanotubes (CNTs) has been synthesized through a facile hydrothermal method. Shape, quantum states, optical behavior and phase purity have been elucidated using SEM, TEM, XPS, UV-DRD, PL and XRD spectra, respectively. Among all, Ni 3 S 2 /CNT50 composite counter electrode delivers the highest Power Conversion Efficiency (PCE) of 9.28 ± 0.03% with a short circuit current (J SC ) of 18.46 ± 0.01 mAcm −2 and open-circuit voltage (V OC ) of 0.73 ± 0.01 V. The improvement observed is due to the lower peak-to-peak separation (E pp ), higher exchange current density (J 0 ) and lower charge transfer resistance (R CT ). External quantum efficiency and electrochemical impedance analysis for the boost in efficiency and improved electrocatalytic activity with low charge-transfer resistance at (CE)/electrolyte interface are well in support for the synergistic effect of Ni 3 S 2 and MWCNTs.

Preparation of ZnO/TiO2 Nanocomposite Sensitized Mangosteen Rind (Garcinia mangostana L) Dye for Light Harvesting Efficiency in Solar Cell

The preparation of ZnO/TiO2 nanocomposite is done using the sol-gel method for light harvesting in dye-sensitized solar cell (DSSC). The titanium dioxide (TiO2) compound was added with different ratios to the ZnO matrix and measured its effect on solar cells based on the DSSC system. The powder X-ray diffractions of nanocomposite revealed anatase (TiO2­) and wurtzite (ZnO­) phases have the highest peak at 25.26° and 36.97°, respectively. The energy gap was observed by diffuse reflectance-ultra violet (DR-UV) spectroscopy and it revealed that the optimum performance of nanocomposite was 3.16 eV for the 1:2 ratio. The optimum power efficiency was 2.4% with 3.6 cm2 active area, Voc= 788 mV and Isc=3.39 mA, respectively. The scanning electron microscope-energy dispersive X-ray (SEM-EDX) demonstrated the diversity of surface morphology depends on the ratio of TiO2 in the nanocomposite. This shows the addition of TiO2 to the ZnO matrix influenced the structure of the nanocomposite, which can be applied as DSSC electrodes.

Synthesis of rGO/NiFe2O4 nanocomposite as an alternative counter electrode material to fabricate Pt-free efficient dye sensitized solar cells

Reduced graphene oxide/nickel ferrite (rNiF) nanocomposites via one pot hydrothermal procedure were synthesised. The synthesised rNiF composite was used as a catalytic counter electrode (CE) material for dye-sensitized solar cell (DSSC). HR-TEM results demonstrates that rNiF composites were firmly enfolded on rGO network, allowing easy electron transfer across the CE-electrolyte interface. The XPS survey scan spectrum of samples demonstrates that the presence of Ni, Fe, C and O in the composite structure. The large amount of porosity and specific surface area was achieved 241.71 (m2/g) and 0.521 (cc/g) by rNiF-25 sample. When rNiF-25 nanocomposite was employed as the CE catalyst in iodine electrolytes, the DSSCs achieved a power conversion efficiency (PCE) of η = 8.41 %, corresponding to 98 % of that of Pt CEs under the illumination. Also, the device maintains 88 % efficiency up to 40 days under ambient conditions without encapsulation. The IPCE of DSSCs for the Pt-based and rNiF-25 based CEs achieves maximum absorption of 81 % and 78 % at 520 nm respectively. The high catalytic activities of rNiF-25 nanocomposite are attributed to synergetic effects from the combination of active NiF structure and conductive graphene which provides efficient charge transport. These findings suggest that rNiF-25 CE can be considered as a promising alternative material to replace Pt counter electrode in DSSCs.

Core-shell structured Ni0.85Se@MoS2 nanosheets anchored on multi-walled carbon nanotubes-based counter electrode for dye-sensitized solar cells

The luxury price and scarcity of noble platinum (Pt) hamper its commercialization in dye-sensitized solar cells (DSSCs). Hence, developing cheap, earth-abundant, and easily available electrocatalyst in lieu of Pt is of great current priority for DSSCs. Herein, core-shell structured Ni0.85Se@MoS2 nanosheets anchored on carboxylic functionalized multi-walled carbon nanotubes (denoted as Ni0.85Se@MoS2@MWCNTs) were prepared via two-step hydrothermal method combined with probe-sonication process. The resultant of Ni0.85Se@MoS2@MWCNTs was successfully characterized by XRD, FESEM, TEM, Raman, and BET analysis. Benefiting from the larger surface areas and more electrolyte adsorption sites, the prepared Ni0.85Se@MoS2@MWCNTs exhibited excellent electrocatalytic performance, electrical conductivity, and electrochemical stability when applied as the counter electrode (CE) for DSSCs. More concretely, the DSSCs assembled with Ni0.85Se@MoS2@MWCNTs delivered remarkable power conversion efficiency (PCE) of 8.98%, exceeding the cell based on Pt CE (6.86%). The combination of Ni0.85Se@MoS2 core-shell structure and MWCNTs provided more active sites, remarkable electric conductivity, and an admirable catalytic property toward the reduction of triiodide. This research suggests a cost-effective strategy to exploring highly effective and robust non-precious-metal CE for their potential application in next-generation energy storage and conversion devices such as DSSCs, water splitting, fuel cells, and other electrochemical applications.

Poly(3,4-ethylenedioxythiophene) decorated MXene as an alternative counter electrode for dye-sensitized solar cells

Counter electrodes (CE) layer in dye-sensitized solar cells (DSSCs) are possibly the most exorbitant material due to the presence of scarce earth metal, platinum (Pt). The prospective substitution of a Pt-CE would effectively pave the way for broad commercialization of the DSSC technology. In this regard, this work is focused on the fabrication of poly(3,4-ethylene dioxythiophene) decorated MXene (PEDOT@Ti3C2Tx) composite electrode, and its performance as a CE in DSSC was tested for the replacement of high-cost Pt-CE. The 2D-Ti3C2Tx was initially synthesized by the selective chemical etching method, followed by the electro-polymerization of 3,4-ethylenedioxythiophene (EDOT) monomer on the Ti3C2Tx surface. Further, X-ray diffraction (XRD), Raman, high-resolution scanning electron microscopy (HR-SEM), and X-ray photoelectron spectroscopy (XPS) characterization results confirm the successful formation of the PEDOT@Ti3C2Tx composite. PEDOT@Ti3C2Tx-CE display a strong electrocatalytic activity toward the iodide/triiodide electrolyte and good charge transfer kinetics with low charge transfer resistance close to the performance of the Pt electrode, as shown by electrochemical experiments. On the other hand, further testing of the device fabricated with thermally decomposed Pt-CE DSSCs achieved an efficiency of 8.7% under simulated 1SUN light at AM1.5G, whilst the DSSC built with the as-prepared composite material had 7.12% efficiency under the same conditions. PEDOT@Ti3C2Tx-CE composite DSSC outperformed PEDOT-CE and Ti3C2Tx-CE DSSC in power conversion efficiency improvements (PCE), demonstrating that PEDOT@Ti3C2Tx composite possesses a strong catalytic activity with noticeable charge transfer and mass transport capabilities. Therefore, the as-fabricated composite film takes utilization of the conductivity and electrocatalytic capabilities of the two components, increasing the overall power conversion efficiency of DSSC. The 15-days stability investigation demonstrates that the PEDOT@Ti3C2Tx-CE-based DSSC exhibits a consistent performance and corrosion resistant toward the iodide/triiodide redox electrolyte. Therefore, overall performance level of the PEDOT@Ti3C2Tx-CE thus entices more study for the replacement of Pt in DSSC and is indeed evinced to be a prospective noble metal electrode contender.