Polypyrrole/Ionic Liquid/Au Nanoparticle Counter-Electrodes for Dye-Sensitized Solar Cells: Improving Charge-Transfer Resistance at the CE/Electrolyte Interface

The dye-sensitized solar cells (DSCs) equipped with mesocarbon microbead (MCMB)-based counter electrodes were explored to examine their cell performance. Three types of nanosized additives including platinum, carbon nanotubes (CNTs), and carbon black (CB) are well dispersed and coated over microscaled MCMB powders. In the design of the counter electrodes, the MCMB graphite offers an excellent medium that allows charge transfer from the ITO substrate to the dye molecule. The active materials such as Pt, CNT, and nanosize CB act as an active site provider for the redox reaction. Among these counter electrodes, the DSCs fabricated with CB electrode exhibit the highest power conversion efficiency. This improved efficiency can be attributed to the fact that the CB nanoparticles not only offer a large number of catalytic sites but also low charge transfer resistance, facilitating a rapid reaction kinetics. Such design of carbon counter electrode has been confirmed to be a promising candidate for replacing Pt electrodes.

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Influence of the interfacial charge-transfer resistance at the counter electrode in dye-sensitized solar cells employing cobalt redox shuttles

Energy & Environmental Science ◽

10.1039/c1ee02389f ◽

2011 ◽

Vol 4 (12) ◽

pp. 4921 ◽

Cited By ~ 165

Author(s):

Hoi Nok Tsao ◽

Julian Burschka ◽

Chenyi Yi ◽

Florian Kessler ◽

Mohammad K. Nazeeruddin ◽

...

Keyword(s):

Solar Cells ◽

Charge Transfer ◽

Counter Electrode ◽

Dye Sensitized Solar Cells ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Dye Sensitized ◽

Redox Shuttles ◽

Sensitized Solar Cells ◽

Interfacial Charge

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Electrochemical, Structural and Morphological Characterization of Hydrothermally Fabricated Binary Palladium Alloys PdCo and PdNi

Metals ◽

10.3390/met9070796 ◽

2019 ◽

Vol 9 (7) ◽

pp. 796

Author(s):

Edson Meyer ◽

Raymond Taziwa ◽

Dorcas Mutukwa ◽

Nyengerai Zingwe

Keyword(s):

Solar Cells ◽

Charge Transfer ◽

Binary Alloys ◽

Dye Sensitized Solar Cells ◽

Charge Transfer Resistance ◽

Palladium Alloys ◽

Transfer Resistance ◽

Dye Sensitized ◽

Sensitized Solar Cells

This article details the development and characterization of binary palladium alloys synthesized via a hydrothermal process. Palladium alloys, being good redox catalysts, could potentially replace platinum in many applications such as in dye sensitized solar cells, capacitors and vehicular catalytic converters where platinum is vital for maximum productivity. A good replacement should be cheap, readily available and be able to offer comparable catalytic activity to that of platinum. As such we hereby attempt to hydrothermally fabricate and characterize binary palladium alloys PdNi and PdCo that could be ideal replacements for platinum. XRD analysis of the as-synthesized binary alloys revealed the existence of only palladium peaks at 2θ values of 40.1°, 46.7°, 68.1°, 82.1° and 86.6°, indicative of the successful formation of the binary alloys. SEM micrographs revealed that both alloys consisted of spherical particles with PdCo agglomerating to an extent, whereas PdNi was widely distributed, thus it could enhance electrolyte adsorption during catalytic reduction reactions. Cyclic voltammetry analysis at 50 mV∙s−1 revealed that PdNi is more electrocatalytically active with a reduction current density of 41 mA∙cm−2 compared to 18 mA∙cm−2 for PdCo. Lower charge transfer resistance from electrochemical impedance spectroscopy confirmed the superior catalytic ability of PdNi. The two palladium alloys also produced maximum specific capacitances of 68 and 27 F∙g−1 for PdNi and PdCo respectively. Analysis of the sample stability yielded coulombic efficiency retention of 98.7 and 97% for PdNi and PdCo respectively after 1000 cycles. Results obtained have shown that the palladium alloys with their low charge transfer resistance could be ideal replacements for platinum in dye sensitized solar cells. Modest specific capacitance for PdNi illustrates its potential as an electrode catalyst in capacitors.

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Low-Cost and Efficient Nickel Nitroprusside/Graphene Nanohybrid Electrocatalysts as Counter Electrodes for Dye-Sensitized Solar Cells

Materials ◽

10.3390/ma14216563 ◽

2021 ◽

Vol 14 (21) ◽

pp. 6563

Author(s):

Md. Mahbubur Rahman

Keyword(s):

Solar Cells ◽

Low Cost ◽

Photovoltaic Performance ◽

Dye Sensitized Solar Cells ◽

Solution Process ◽

Charge Transfer Resistance ◽

Counter Electrodes ◽

Transfer Resistance ◽

Dye Sensitized ◽

Sensitized Solar Cells

Novel nickel nitroprusside (NNP) nanoparticles with incorporated graphene nanoplatelets (NNP/GnP) were used for the first time as a low-cost and effective counter electrode (CE) for dye-sensitized solar cells (DSSCs). NNP was synthesized at a low-temperature (25 °C) solution process with suitable purity and crystallinity with a size range from 5 to 10 nm, as confirmed by different spectroscopic and microscopic analyses. The incorporation of an optimized amount of GnP (0.2 wt%) into the NNP significantly improved the electrocatalytic behavior for the redox reaction of iodide (I-)/tri-iodide (I3-) by decreasing the charge-transfer resistance at the CE/electrolyte interface, lower than the NNP- and GnP-CEs, and comparable to the Pt-CE. The NNP/GnP nanohybrid CE when applied in DSSC exhibited a PCE of 6.13% (under one sun illumination conditions) with the Jsc, Voc, and FF of 14.22 mA/cm2, 0.628 V, and 68.68%, respectively, while the PCE of the reference Pt-CE-based DSSC was 6.37% (Jsc = 14.47 mA/cm2, Voc = 0.635 V, and FF = 69.20%). The low cost of the NNP/GnP hybrid CE with comparable photovoltaic performance to Pt-CE can be potentially exploited as a suitable replacement of Pt-CE in DSSCs.

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Preparation of Nano-Ag-TiO2 Composites by Co-60 Gamma Irradiation to Enhance the Photocurrent of Dye-Sensitized Solar Cells

International Journal of Photoenergy ◽

10.1155/2019/5737952 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8

Author(s):

Le Thanh Nguyen Huynh ◽

Viet Hai Le ◽

Thanh Long Vo ◽

Thi Kim Lan Nguyen ◽

Quoc Hien Nguyen ◽

...

Keyword(s):

Solar Cells ◽

Charge Transfer ◽

Electrochemical Impedance ◽

Dye Sensitized Solar Cells ◽

Energy Conversion Efficiency ◽

Charge Transfer Resistance ◽

Open Circuit ◽

Transfer Resistance ◽

Dye Sensitized ◽

Sensitized Solar Cells

Nano-silver-titanium dioxide (Ag-TiO2) composites were prepared from commercial TiO2 (P25, Degussa) and silver nitrate (AgNO3) by gamma Co-60 irradiation method with various initial concentrations of AgNO3. The nano-AgTiO2 composites are utilized as the photoanode for dye-sensitized solar cells (DSCs). Under full sunlight illumination (1000 W/m2, AM 1.5), the efficiency of DSCs has improved significantly despite the Ag content of below 1%. The DSC—assembled with 0.75 Ag-TiO2 (0.75% Ag) photoanode—showed that the photocurrent was significantly enhanced from 8.1 mA.cm−2 to 9.5 mA.cm−2 compared to the DSCs using bared TiO2 photoanode. The unchanged open-circuit voltage resulted in the overall energy conversion efficiency to be increased by 25% from 3.75% to 4.86%. Electrochemical impedance spectroscopy (EIS) analysis showed that the charge transfer resistance is reduced when increasing Ag content, demonstrating that the charge transfer at TiO2/dye interface was enhanced in the presence of silver nanoparticles.

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Copolymer-templated nitrogen-enriched nanocarbons as a low charge-transfer resistance and highly stable alternative to platinum cathodes in dye-sensitized solar cells

Journal of Materials Chemistry A ◽

10.1039/c4ta07012g ◽

2015 ◽

Vol 3 (8) ◽

pp. 4413-4419 ◽

Cited By ~ 29

Author(s):

Myung Jong Ju ◽

In Taek Choi ◽

Mingjiang Zhong ◽

Kimin Lim ◽

Jaejung Ko ◽

...

Keyword(s):

Solar Cells ◽

Charge Transfer ◽

Block Copolymers ◽

High Performance ◽

Dye Sensitized Solar Cells ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Dye Sensitized ◽

Low Charge ◽

Sensitized Solar Cells

High performance N-enriched nanocarbon CEs for organic DSSCs were synthesized by pyrolysis of self-assembled block copolymers.

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Electrochemically Deposited Polypyrrole for Dye-Sensitized Solar Cell Counter Electrodes

International Journal of Photoenergy ◽

10.1155/2012/671326 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 18

Author(s):

Khamsone Keothongkham ◽

Samuk Pimanpang ◽

Wasan Maiaugree ◽

Saman Saekow ◽

Wirat Jarernboon ◽

...

Keyword(s):

Solar Cells ◽

Direct Current ◽

Dye Sensitized Solar Cells ◽

Charge Transfer Resistance ◽

Counter Electrodes ◽

Transfer Resistance ◽

Dye Sensitized ◽

Conductive Glass ◽

Alternative Current ◽

Sensitized Solar Cells

Polypyrrole films were coated on conductive glass by electrochemical deposition (alternative current or direct current process). They were then used as the dye-sensitized solar cell counter electrodes. Scanning electron microscopy revealed that polypyrrole forms a nanoparticle-like structure on the conductive glass. The amount of deposited polypyrrole (or film thickness) increased with the deposition duration, and the performance of polypyrrole based-dye-sensitized solar cells is dependant upon polymer thickness. The highest efficiency of alternative current and direct current polypyrrole based-dye-sensitized solar cells (DSSCs) is 4.72% and 4.02%, respectively. Electrochemical impedance spectroscopy suggests that the superior performance of alternative current polypyrrole solar cells is due to their lower charge-transfer resistance between counter electrode and electrolyte. The large charge-transfer resistance of direct current solar cells is attributed to the formation of unbounded polypyrrole chains minimizing theI3 −reduction rate.

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