Transparent Graphene-Platinum Films for Advancing the Performance of Dye-Sensitized Solar Cells

ABSTRACTTransparent films of platinum nanoparticles on graphene nanohybrids were synthesized in a two-step process. Reduction of homogeneously dispersed Pt precursor and graphene in water and solution coating/annealing afforded thin films with high catalytic performance as counter electrodes in dye-sensitized solar cells (DSSC). The requisite dispersant consisting of poly(oxyethylene)-(POE) segments and cyclic imide functionalities allowed the in-situ reduction of dihydrogen hexachloroplatinate by ethanol and the formation of nanohybrids of graphene-supported Pt nanoparticles at 4.0 nm diameter. Characterizations of polymeric dispersants by Fourier-transform infrared spectroscopy, thermogravimetric analysis, and nanohybrids by transmission electron microscope were performed. After screening various compositions of Pt/graphene, the nanohybrid film at the specific ratio of 5/1 by weight was fabricated into a counter electrode (CE) for DSSC by the solution casting method. The evaluation of cell performance demonstrated the most improved power conversion efficiency of 8.00%. This is significant achievement in comparison with 7.14% for the DSSC with the conventional platinum sputtered CE. Furthermore, the solution casting method allows the preparation of transparent CE films that are suitable for using as rear-illuminated DSSC. The approach was proven to be feasible by measuring the cell efficiency under rear light illumination. The power efficiency up to 7.01%, comparable to 8.00% by a normally front illumination, has been accomplished. In contrast, the rear illumination at merely 2.36% efficiency was obtained for the DSSC with sputtered platinum CE. Analyses of cyclic voltammetry, electrochemical impedance spectra were well correlated to the high efficiency of the performance caused by this nanohybrid film.

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Study on the Change in Photovoltage by Control of Cell Gap in Dye-Sensitized Solar Cells

Journal of Solar Energy Engineering ◽

10.1115/1.4001151 ◽

2010 ◽

Vol 132 (2) ◽

Cited By ~ 2

Author(s):

Chaehyeon Lee ◽

Weekyung Kang ◽

Min Jae Ko ◽

Kyoungkon Kim ◽

Nam-Gyu Park

Keyword(s):

Solar Cells ◽

Electrochemical Impedance ◽

Dye Sensitized Solar Cells ◽

Energy Conversion Efficiency ◽

Open Circuit ◽

Electrolyte System ◽

Counter Electrodes ◽

Dye Sensitized ◽

Transient Photovoltage ◽

Sensitized Solar Cells

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.

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Self-Assembly Synthesis of the MoS2/PtCo Alloy Counter Electrodes for High-Efficiency and Stable Low-Cost Dye-Sensitized Solar Cells

Nanomaterials ◽

10.3390/nano10091725 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1725 ◽

Cited By ~ 2

Author(s):

Zhi Zeng ◽

Dongbo Wang ◽

Jinzhong Wang ◽

Shujie Jiao ◽

Yuewu Huang ◽

...

Keyword(s):

Solar Cells ◽

Electrocatalytic Activity ◽

High Efficiency ◽

Electrochemical Impedance ◽

Dye Sensitized Solar Cells ◽

Counter Electrodes ◽

Transfer Resistance ◽

Dye Sensitized ◽

Sensitized Solar Cells ◽

Ptco Alloy

In this work, MoS2 microspheres/PtCo-alloy nanoparticles (MoS2/PtCo-alloy NPs) were composited via a novel and facile process which MoS2 is functionalized by poly (N-vinyl-2-pyrrolidone) (PVP) and self-assembled with PtCo-alloy NPs. This new composite shows excellent electrocatalytic activity and great potential for dye-sensitized solar cells (DSSCs) as a counter electrode (CE) material. Benefiting from heterostructure and synergistic effects, the MoS2/PtCo-alloy NPs exhibit high electrocatalytic activity, low charge-transfer resistance and stability in the cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) test. Meanwhile, a high power-conversion efficiency (PCE) of 8.46% is achieved in DSSCs with MoS2/PtCo-alloy NP CEs, which are comparable to traditional Pt CEs (8.45%). This novel composite provides a new high-performance, stable and cheap choice for CEs in DSSCs.

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Fabrication of the Effective Counter Electrode for Dye-Sensitized Solar Cells

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.197-198.1143 ◽

2011 ◽

Vol 197-198 ◽

pp. 1143-1146 ◽

Cited By ~ 3

Author(s):

Rui Liu ◽

Wein Duo Yang ◽

Jian Fu Wu ◽

Liang Sheng Qiang

Keyword(s):

Solar Cells ◽

Spin Coating ◽

Electrochemical Impedance ◽

Dye Sensitized Solar Cells ◽

Dip Coating ◽

Counter Electrodes ◽

Dye Sensitized ◽

Coating Method ◽

Sensitized Solar Cells ◽

Energy Disperse Spectroscopy

Pt-counter electrodes were manufactured by dip coating, spin coating and sputtering methods for dye-sensitized solar cells (DSSCs). Their properties were analyzed with cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), energy disperse spectroscopy (EDS). We also fabricated the TiO2 nanotubes of 1.04 μm length as photoanode. The analytic results show that spin coating method has higher Pt content deposited on FTO glass, better performance of charge-transfer, more positive potential of tri-iodide reduction and higher efficiency of DSSCs.

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