Electrodes For Solar Cells Research Articles

Multi-layer transparent electrodes for high performance bifacial perovskite solar cells

Bifacial perovskite solar cells have gained significant interest due to their high light-harvesting capabilities. In this study, a multilayer transparent conducting film (MLTCF) composed of indium tin oxide (ITO)/2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP)/Ag/ITO is developed as a top electrode for bifacial perovskite solar cells (PSCs). By applying BCP at the bottom of the ITO layer as an adhesion promoter, the Volmer–Weber mechanism of island growth pattern for Ag under thickness threshold conditions is successfully suppressed. This results in ultra-thin (8 nm) and ultra-smooth Ag films with a relatively low sheet resistance of 5.5 Ω/sq and high transmittance of 85.8 % at a typical wavelength of 550 nm. Furthermore, a molybdenum oxide (MoO3) overlayer is evaporated onto the soft organic charge transport layer as a protective buffer to prevent sputtering damage during the deposition of ITO and Ag films. Consequently, bifacial PSCs exhibit an optimized power conversion efficiency (PCE) of 20.3% for single-side illumination from the glass side, and equivalent PCEs of 23.6 %, 25.2 %, 26.8 % with albedo of 0.2, 0.3 and 0.4, respectively. This work paves the way for the development of highly efficient bifacial thin-film solar cells.

Inexpensive green synthesis of natural dye-sensitized solar cells with aqueous solution as a Bi2S3 counter electrode

Natural dyes are more environmentally and fiscally friendly than ruthenium-based dyes because they are non-toxic and inexpensive. In this research, dye-sensitized solar cells (DSSCs) were created using natural dyes as light harvesting materials. Natural dyes were derived from blackberry fruit, beetroot, and neem foliage. Also, organic-solvent and water-based electrolytes were investigated for the TiO2 working electrode and Bi2S3 counter electrode. As-prepared organic-solvent-based electrolyte DSSCs demonstrated photoelectrochemical efficiency with fill factors (FF) varying from 35% to 45%. At 100 mW/cm2 light strength, open circuit voltages (VOC) and short circuit current densities (JSC) vary from 0.41 to 0.58 V and 1.35–1.93 mA cm−2, respectively. As a result of this, the highest power conversion efficiency (ƞ) of the as-prepared blackberry DSSC is 0.51%. The highest power conversion efficacy using water-based electrolytes with berries dye and a comparable extraction solvent, on the other hand, reached up to 0.47%. This is the first research to describe the construction of a dye-sensitized solar cell using natural dye sensitizers extracted from various colours of fruit and foliage in the presence of organic-solvent and aqueous electrolyte with Bi2S3 as a counter electrode for an efficient dye-sensitized solar cell.

Innovative PANI/g-C3N4@rGO nanocomposite electrode for improved energy storage and conversion applications

We successfully synthesized a ternary conducting polymer nanocomposite using an in-situ oxidative polymerization method, incorporating polyaniline, graphitic carbon nitride, and reduced graphene oxide. This nanocomposite serves as a bifunctional electrode for applications in energy storage and conversion. The as-prepared PANI nanocomposite exhibited excellent storage properties, with a specific capacitance of 442 F/g in 1 M H2SO4 as an electrolyte in the presence of graphitic-C3N4@reduced graphene oxide. This is a significant enhancement over the specific capacitance of pure PANI, which is typically∼200 F/g. Interestingly, the PANI/graphitic-C3N4@reduced graphene oxide electrode exhibited better cycling stability with 90% retention of the specific capacitance after 5000 cycles at a current density of 2.5 A/g. Furthermore, when employed as a counter electrode for dye-sensitized solar cells (DSSC), it exhibits excellent electrocatalytic activity, which is attributed to its large specific surface area and superior electrocatalytic activity. The dye-sensitized TiO2 photoanodes were sandwiched between CEs using a PEO-based gel electrolyte, and photovoltaic studies were performed under simulated illumination of 100 mW/cm2. The dye sensitized solar cell exhibited the short circuit current density (Jsc) 13.5 mA/cm2 and open circuit voltage (Voc) 0.76 V with power conversion efficiency of 6 %.

Nitrogen, sulfur coordinated metal complex and reduced graphene oxide hybrid materials as counter electrodes for application in dye-sensitized solar cells

Graphene, as one of the carbon-based materials, is considered to be a potential replacement for platinum and has been widely used as a counter electrode in dye-sensitized solar cells to achieve low-cost and high electrocatalytic materials. In this work, we synthesized a nitrogen-sulfur-coordinated iron complex as a source of heteroatoms, and prepared iron-nitrogen-sulfur co-doped reduced graphene oxide (FeNS-rGO) composite material by mixing with different mass ratios of graphene oxide (GO) and thermal annealing under nitrogen at 400 °C. The sintered GO was transformed into rGO, which increased the conductivity of materials, while the doping of nitrogen and sulfur atoms enhanced the carrier mobility and conductivity of the material. The distribution of Fe on graphene also improved the catalytic performance of material. FeNS-rGO (5:1), used as the CE in DSSC, showed superior reduction catalytic activity for I−/I3− compared to platinum and demonstrated an excellent power conversion efficiency of 8.17 %, which outperformed platinum. This proves that the graphene composite material doped with iron, nitrogen, and sulfur has excellent performance and can be used as a substitute for platinum.

Electrodeposited polyaniline based carbon nanotubes fiber as efficient counter electrode in wire-shaped dye sensitized solar cells

Electrodeposited polyaniline over the carbon nanotubes fiber (CNTF) has been investigated as potential candidate to substitutes the Pt based auxiliary electrodes in unidimensional fibrous solar cells. CNTF, with excellent electrical and mechanical properties, modified with conducting polymer (polyaniline) via facile electrodeposition process which employed as cathodic materials showed efficient electrochemical reduction of triiodide ions in the fiber shaped dye-sensitized solar cells. Scanning electron microscopic analysis showed the efficacious integration of conducting polymer over the CNTF surface. The admirable electrocatalytic behavior of the fabricated electrode has investigated by electrochemical impedance spectroscopy and cyclic voltammetry. Current density and voltage (J–V) curves are used to quantify the photovoltaic performance of devices with different counter electrodes with fixed photoanode. With lower peak to peak separation, improved current density and better fill factor, exhibited the superior efficiency of modified electrode (PANI@CNTF). As compared to pristine fiber, polyaniline modification showed the outstanding performance with improved photovoltaics and electrochemical parameters measured by the J–V and CV curves, respectively.

Liquid Metal‐Based Perovskite Solar Cells: In Situ Formed Gallium Oxide Interlayer Improves Stability and Efficiency

AbstractIn this study, eutectic gallium–indium alloy (EGaIn) liquid metal is used as the rear electrode for perovskite solar cells (PSCs), where the interfacial properties of the device, particularly the beneficial roles of the surface oxide of the liquid metal, are explored. The findings demonstrate that the native oxide of the EGaIn electrode significantly affects the stability of photovoltaic performance and impedance characteristics including series and shunt resistances. Based on the results, the following hypothesis is formulated: the oxide interlayer serves two crucial functions of a barrier against metal diffusion and a tunnel for enhancing charge extraction and transfer. The results of elemental mapping and trap density calculation support the former function of the hypothesis that the oxide film can effectively prevent metal penetration into the perovskite layer. Furthermore, measurements involving capacitance−voltage and time‐resolved photoluminescence confirm that the oxide film on the liquid metal eliminates the interfacial Schottky barrier, promoting efficient charge extraction and transfer processes. Finally, the investigation is extended to develop flexible PSCs using the EGaIn electrode, which consistently exhibits stable performance during repeated bending cycles. Notably, the EGaIn rear electrode can be readily removed and collected through a straightforward acid treatment, offering a promising avenue for efficient cell recycling.

Characterization of carbon derived from candle by flame-soot method for counter electrodes of dye-sensitized solar cells

Candle soot, carbon samples prepared by flame-soot method, was characterized and investigated for its catalytic ability for the reduction of tri-iodide ions aiming to substitute expensive platinum based electrode used in dye-sensitized solar cells (DSCs). The Energy Dispersive X-ray Spectroscopy of the candle soot samples revealed that the soot contains 96% carbon. Similarly, Scanning Electron Microscopy images show that the candle soot consists of interconnected carbon nanoparticles of size ∼50 nm. Furthermore, X-ray Diffraction and Raman spectroscopy showed that the candle soot consists of disordered and ordered graphitic carbons in a comparable proportion. The catalytic ability of the candle soot was compared with that of platinum by Electrochemical Impedance Spectroscopy of the symmetrical electrochemical cells. The charge transfer resistance (Rct) at the candle soot-electrolyte interface was observed to be ∼4.42 Ω cm2 compared to ∼ 5.04 Ω cm2 that of the platinum-electrolyte interface. The candle soot was prepared by a simple method using low-cost material; hence, it can be a low-cost and efficient counter electrode material alternate to the platinum used in counter electrodes of DSCs.

Sintering densification of ITO targets with low tin oxide content for depositing TCO films as electrodes of solar cells

Highly efficient solar cells demand transparent and conductive oxide films with high electronic mobility. Decreasing SnO2 content in In2O3 targets (ITO) is one of important ways, but resulting in difficulty of sintering densification. ITO targets with SnO2 contents of 1 wt%, 2 wt.% and 3 wt% were prepared by microwave sintering. Harmless sintering additives of TiO2 and trances of SiO2 promotes sintering densification. All the targets show the cubic bixbyite phase and dense microstructure. The fine grains with the average size of several microns were obtained. Higher sintering temperature contributes to eliminating the pores in targets, enhancing density and decreasing resistivity. The optimal sintering temperature of 1550 °C obtains the highest relative density (>99 %) and low resistivity (<3.4 × 10−4 Ω cm). The enhanced density of these ITO targets with low SnO2 content can effectively inhibit the formation of nodules on the surface of target during magnetron sputtering.

Enhancing dye-sensitized solar cell performance by employing an innovative WSe2:Zn counter electrode for improved electrocatalytic activity

In this research, we introduced a novel counter electrode (CE) for dye-sensitized solar cells (DSSCs) based on crystalline WSe2 doped with Zn impurities. The crystalline nature of these CEs was confirmed through X-ray diffraction (XRD) analysis. Additionally, we demonstrated that Zn dopants significantly enhances the electrochemical and electrocatalytic properties of the CEs. These improvements were verified using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and Tafel analysis with iodine-based electrolytes. Collectively, these enhancements resulted in a remarkable 42 % increase in DSSC efficiency, improving it from 5.78 % to 8.19 % under optimized conditions. Notably, this surpassed the performance of platinum-based CEs, which achieved 7.66 % efficiency. The proposed CE holds great promise for advancing DSSCs by elevating their efficiency and reducing fabrication costs.

Highly efficient nitrogen-doped reduced graphene oxide-Sr0.7Sm0.3Fe0.4Co0.6O2.65 nanocomposites utilized as a counter electrode in dye-sensitized solar cells

Dye-sensitized solar cells (DSSCs) are known for their aesthetic properties, not limited to colour tuneability and transparency, but are also promising renewable energy technology that can efficiently harvest sunlight to generate electricity without releasing toxic gases. DSSCs are one of the potential candidates for fabricating colourful and see-through solar cells for energy-harvesting aesthetic windows. However, a trade-off between transparency and power conversion efficiency (PCE) has to be tackled amicably to realize solar cells with good PCE and transparency. Judicious selection of dyes to bypass light absorption in the high eye-sensitivity region (500 – 600 nm) is one of the plausible solutions. Most importantly, developing novel counter electrode materials using facile preparation techniques, low-cost materials, and environmentally friendly conditions helps overcome the limitations of commonly used but expensive and corroding metals, thereby improving the PCE of DSSCs. Herein, we report the synthesis of a novel hybrid nitrogen-doped reduced graphene oxide-Sr0.7Sm0.3Fe0.4Co0.6O2.65 (N-RGO-SSFC) nanocomposite using the thermal treatment method. The N-RGO-SSFC nanocomposites were characterized using microscopic and spectroscopic techniques and applied as counter electrodes in DSSCs. Scanning electron microscopy images revealed the presence of N-RGO sheets decorated by SSFC nanoparticles. The introduction of SSFC nanoparticles onto N-RGO sheets led to the formation of nanocomposites with a tetragonal structure, a surface area of 178.0 m2 g-1, an electrical conductivity of 13.02 S cm-1, and a charge transfer resistance of 10.6 Ω. The N-RGO-SSFC nanocomposite counter electrodes resulted in DSSCs with an enhanced PCE of 6.64% due to the formation of excellent electron transfer pathways. This outperformed DSSCs based on the Pt reference electrode with a PCE of 5.52%. Hence, N-RGO-SSFC nanocomposites can be applied as a potential counter-electrode material in DSSCs.

Platinum nanoparticles decorated multiwalled carbon nanotube composites as highly transparent, bifacial counter electrodes for dye-sensitized solar cells

Dye-sensitized solar cells (DSSCs) are low-cost solar energy conversion devices with variable color and transparency advantages. DSSCs' potential power efficiency output, even in diffuse light conditions with consistent performance, allows them to be used in building-integrated photovoltaics (BIPV) window applications. Significantly, the development of bifacial DSSCs is getting significant scientific consideration. Triiodide/iodide (I3–/I–) redox couple-mediated DSSCs require highly effective and stable electrocatalysts for I3− reduction to overcome their performance constraints. However, the commonly employed platinum (Pt) cathodes have restrictions on high price and unfavorable durability. Here, we report platinum nanoparticles (Pt NPs) incorporated into multiwalled carbon nanotubes (MWCNT) composites with lower Pt content as an efficient bifacial counter electrode (CE) material for DSSC applications. Pt NPs were homogenously decorated over the MWCNT surfaces using a simple polyol method at relatively low temperatures. CEs fabricated using Pt/MWCNT composites exhibited excellent transparency and power conversion efficiencies (PCE) of 6.92% and 6.09% for front and rear illumination. The results are expected to bring significant advances in bifacial DSSCs for real-world window applications.

Bi2S3 nanoparticles anchored MWCNTs towards core-shell architecture: Counter electrode for dye-sensitized solar cell

A core-shell surface architecture has been developed through cost-effective and efficient sequential growth controlled chemical route, namely; successive ionic layer adsorption and reaction (SILAR) method to anchor Bi2S3 nanoparticles as shell over pre-coated MWCNTs as core to serve as a counter electrode (CE) in dye-sensitized solar cells (DSSCs) with eosin-Y dye loaded ZnO as photoanode, and polyiodide as liquid electrolyte. Electrochemical and device performance studies have been used to yield optimum growth through the number of SILAR cycles of Bi2S3 over MWCNTs. Electrochemical impedance spectroscopy (EIS) analysis revealed that, for well-optimized MWCNTs/Bi2S3 core-shell based device, the synergistic effect at the CE/electrolyte interface not only results in lower charge transfer resistance and faster electron transfer from CE to the electrolyte but equally doubled efficiency (0.343 %) than bare MWCNTs (0.162 %) and eight-fold enhanced efficiency than bare Bi2S3 (0.040 %).

Facile fabrication of conductive graphitic carbon films as transparent electrodes in organic solar cells by ion beam irradiation of polystyrene films and carbonization

Conductive graphitic carbon films were fabricated from insulating polystyrene (PS) by ion beam irradiation and subsequent thermal treatment, and used as a transparent anode for organic solar cells (OSCs). Analyses of optical and chemical properties revealed that the thermally resistant oxidized carbon clusters in the PS precursors (spin-coated on quartz) were efficiently generated by ion beam irradiation at a fluence of 2 x 1016 ions/cm2, and transformed to graphitic carbon thin films through high-temperature treatment. The graphitic carbon films exhibited thickness-dependent conductivity (the highest conductivity of 374 S/cm), while their work function (5.20 eV) and surface roughness (0.560–0.596 nm) were unaffected by the thickness of the films. Furthermore, the introduction of the 10.2 nm-thick graphitic carbon films into poly(3-hexylthiophene) (P3HT): [6,6]-phenyl-C61 butyric acid methyl ester (PCBM)-based OSCs resulted in a power conversion efficiency (PCE) of 1.40%, demonstrating the feasibility of using the graphitic carbon films as transparent electrodes.

Nanograss-Assembled NiCo2S4 as an Efficient Platinum-Free Counter Electrode for Dye-Sensitized Solar Cell.

Dye-sensitized solar cells (DSSCs) are often viewed as the potential future of photovoltaic systems and have garnered significant attention in solar energy research. In this groundbreaking research, we introduced a novel solvothermal method to fabricate a unique "grass-like" pattern on fluorine-doped tin oxide glass (FTO), specifically designed for use as a counter electrode in dye-sensitized solar cell (DSSC) assemblies. Through rigorous structural and morphological evaluations, we ascertained the successful deposition of nickel cobalt sulfide (NCS) on the FTO surface, exhibiting the desired grass-like morphology. Electrocatalytic performance assessment of the developed NCS-1 showed results that intriguingly rivaled those of the acclaimed platinum catalyst, especially during the conversion of I3 to I- as observed through cyclic voltammetry. Remarkably, when integrated into a solar cell assembly, both NCS-1 and NCS-2 electrodes exhibited encouraging power conversion efficiencies of 6.60% and 6.29%, respectively. These results become particularly noteworthy when compared to the 7.19% efficiency of a conventional Pt-based electrode under similar testing conditions. Central to the performance of the NCS-1 and NCS-2 electrodes is their unique thin and sharp grass-like morphology. This structure, vividly showcased through scanning electron microscopy, provides a vast surface area and an abundance of catalytic sites, pivotal for the catalytic reactions involving the electrolytes in DSSCs. In summation, given their innovative synthesis approach, affordability, and remarkable electrocatalytic attributes, the newly developed NCS counter electrodes stand out as potent contenders in future dye-sensitized solar cell applications.

Iron alloying improved electrocatalytic activity of Cu2Cu1−xFexSnS4 counter electrodes in dye-sensitized solar cells

Iron alloying improved electrocatalytic activity of Cu2Cu1−xFexSnS4 counter electrodes in dye-sensitized solar cells

Design and fabrication of BaSnO3/RGO as efficient Pt-free counter electrode for dye-sensitized solar cells

Design and fabrication of BaSnO3/RGO as efficient Pt-free counter electrode for dye-sensitized solar cells

Experimental and computational investigation of multi-walled carbon nanotubes decorated by Co–Ni–Se@MoSe2 core–shell as a sustainable counter electrode for dye-sensitized solar cells

The development of a highly active, long-lasting, and cost-effective electrocatalyst as an alternative to platinum (Pt) is a vital issue for the commercialization of dye-sensitized solar cells (DSSCs). Herein, Co–Ni–Se@MoSe2 core–shell structures decorated on multi-walled carbon nanotubes (MWCNTs) were synthesized for the first time by the hydrothermal and probe-sonication methods. The electrochemical performance of this composite was examined using electrochemical measurement techniques. The results showed improved properties and better electrochemical activities of the Co–Ni–Se@MoSe2@MWCNTs than Pt and other counter electrodes (CEs) for the triiodide reduction and exhibit good electrochemical stability in iodine-based electrolytes. The power conversion efficiency of DSSCs based on Co–Ni–Se@MoSe2@MWCNTs CE reaches 9.43%, significantly superior to that with Co–Ni–Se@MoSe2 core–shell (8.13%), Pt CE (7.44%), and other CEs. The notable performance is attributed to the synergistic effect between Co–Ni–Se@MoSe2 and MWCNTs. As a result, the transfer of electrons to the active site is promoted, the agglomeration of Co–Ni–Se@MoSe2 is hampered, and more active sites are available. Density functional theory calculations revealed that I2 adsorption on MoSe2 surfaces facilitated the generation of I− ions, which played a critical role in enhancing the reaction efficiency. Therefore, the Co–Ni–Se@MoSe2@MWCNTs composite is a promising candidate for use in high-performance DSSCs.

Vanadium Doped CoP on a Carbon Paper Composite as a Counter Electrode for Dye-Sensitized Solar Cells

Vanadium Doped CoP on a Carbon Paper Composite as a Counter Electrode for Dye-Sensitized Solar Cells

Efficient One-Step Synthesis of a Pt-Free Zn0.76Co0.24S Counter Electrode for Dye-Sensitized Solar Cells and Its Versatile Application in Photoelectrochromic Devices.

In this study, we synthesized a ternary transition metal sulfide, Zn0.76Co0.24S (ZCS-CE), using a one-step solvothermal method and explored its potential as a Pt-free counter electrode for dye-sensitized solar cells (DSSCs). Comprehensive investigations were conducted to characterize the structural, morphological, compositional, and electronic properties of the ZCS-CE electrode. These analyses utilized a range of techniques, including X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The electrocatalytic performance of ZCS-CE for the reduction of I3- species in a symmetrical cell configuration was evaluated through electrochemical impedance spectroscopy and cyclic voltammetry. Our findings reveal that ZCS-CE displayed superior electrocatalytic activity and stability when compared to platinum in I-/I3- electrolyte systems. Furthermore, ZCS-CE-based DSSCs achieved power conversion efficiencies on par with their Pt-based counterparts. Additionally, we expanded the applicability of this material by successfully powering an electrochromic cell with ZCS-CE-based DSSCs. This work underscores the versatility of ZCS-CE and establishes it as an economically viable and environmentally friendly alternative to Pt-based counter electrodes in DSSCs and other applications requiring outstanding electrocatalytic performance.

Copper tungstates directly derived from polyoxotungstate-MOF as counter electrodes for dye-sensitized solar cells

The strategically selection of different selection of reaction temperature directly affects the performance of the target catalyst. Herein, copper tungstate species catalysts were directly derived from polyoxotungstate-based metal–organic frameworks ([Cu2(BTC)4/3(H2O)2]6[H3PW12O40], PW12-MOF) as sacrificial template by in-situ pyrolysis at temperatures of 600, 700, 800, 900, 1000 °C under the protection of N2, and further served as counter electrodes (CEs) to assemble dye-sensitized solar cells (DSSCs). The corresponding characterization of XRD, XPS, SEM and N2 adsorption/desorption revealed that PW12-MOF can be converted into copper tungstate, and the ligand groups can be carbonized into graphitic C to embedded in CuWO4, thus forming CuWO4@C composite at 800 °C. The significant effect of different pyrolysis temperatures on the electrocatalytic performance of the prepared CuWO4-based catalysts were identified with cyclic voltammetry, electrochemical impedance spectroscopy and Tafel polarization. Furthermore, five different CuWO4-based catalysts were applied to regenerate I3−/I− shuttles in DSSCs, and then achieved power conversion efficiencies (PCE) of 5.79, 6.39, 7.01, 6.15 and 5.40% by photocurrent-voltage measurement, respectively, which was caused by the enhancement of electrical conductivity and the increase of catalytic active sites by the synergistic effect between CuWO4 and C, illustrating an excellent alternative to Pt CEs in the encapsulated DSSCs.