Tandem Dye-sensitized Solar Cells Research Articles

Selective Synthesis of FeS and FeS2 Nanosheet Films on Iron Substrates as Novel Photocathodes for Tandem Dye-Sensitized Solar Cells

FeS and FeS2 nanosheet films were selectively synthesized on iron substrates through one-step hydrothermal treatment of iron foil and sulfur powder in the presence or absence of hydrazine. The resulting FeSx (x = 1, 2) nanosheet films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) and used as novel photocathodes in tandem solar cells with dye-sensitized TiO2 nanorod films as the corresponding photoanode. The photovoltaic properties of the tandem dye-sensitized solar cells were carefully studied. We found that the performance of the FeS nanosheet film photocathode was better than that of the FeS2 one in the tandem dye-sensitized solar cells. In the case of the FeS nanosheet film photocathode, a short circuit photocurrent (Isc) of 2.53 mA/cm2, an open circuit photovoltage (Voc) of 0.60 V, a fill factor (FF) of 0.31, and conversion efficiency (η) of 1.32% were obtained under an illumination of 100 mW/cm2. This study suggests that ...

Tandem dye-sensitized solar cell-powered electrochromic devices for the photovoltaic-powered smart window

Tandem dye-sensitized solar cell (DSSC)-electrochromic (EC) devices were realized using two-faced transparent conducting oxide (TCO). To supply sufficient voltage to drive the EC devices, two series connected, semitransparent DSSCs were fabricated with 7 nm-thick, dye-adsorbed TiO 2 and 4 nm-thick Pt layers. The two series connected, semitransparent DSSCs that were used had an open circuit voltage and short circuit current density of about 1.35 V and 3.96 mA cm −2, respectively, at 1-sun. The tandem DSSC-EC devices showed an optical density difference of 1.2 at 750 nm and reasonable response times of about 60 and 45 s during the coloring and bleaching processes, respectively, indicating that the two series-connected, semitransparent DSSCs could be used as the power sources in the tandem photovoltaic-powered EC devices.

Preparation and characterization of Eosin B- and Erythrosin J-sensitized nanostructured NiO thin film photocathodes

Nickel oxide (NiO) thin films were prepared onto ITO/glass substrates by spin-coating, dipping and electrochemically. Studies of the morphological and structural properties of the films were done by atomic force microscopy (AFM). Photoelectrochemical and optical experiments were carried out in order to characterize the semiconductor properties of the nanostructured NiO thin films. The experiments were also done for Eosin B- and Erythrosin J-sensitized nanostructured NiO films, with the aim to visualize their potential application as photocatodes in tandem dye-sensitized solar cells (TDSSC). The NiO grown by dipping was the one presenting the best morphological properties. The photoelectrochemical results for all the bare NiO, NiO–Eosin B and NiO–Erythrosin J/electrolyte (I 2/I −) systems showed a p-type behavior. An enhancement in the photocurrent has been observed for the systems sensitized with the dyes. For the NiO/Erythrosin J system the enhancement of the current under illumination in comparison to the dark current was about 200%.

A High Voltage Dye-sensitized Solar Cell using a Nanoporous NiO Photocathode

Abstract An np tandem dye-sensitized solar cell (np-DSC) comprising a titanium dioxide (TiO2) anode and a nickel oxide (NiO) cathode prepared as porous nanostructured films by a sol–gel method using a triblock copolymer template (P123, HO(OCH2CH2)20(OCH(CH3)CH2)70(OCH2CH2)20OH))CH2 exhibited a high open circuit voltage (Voc) of 0.92 V that surpassed the long time champion data, ≈0.8 V for conventional DSC.

Tandem dye-sensitized solar cell for improved power conversion efficiencies

The power conversion efficiency of dye-sensitized solar cells crucially depends on the ability of the sensitizer to absorb light in a broad range of the solar spectrum. In order to increase this range of absorption, a tandem structure with two different sensitizer dyes in two different compartments of the cell, respectively, was realized. Overall power conversion efficiencies as high as η=10.5% and short circuit current densities of JSC=21.1 mA/cm2 were achieved under air mass 1.5 illumination with red dye and black dye in the upper and lower compartment of the cell, respectively.

Dye-sensitized nanostructured tandem cell-first demonstrated cell with a dye-sensitized photocathode

We show that a combination of a dye and a nanostructured NiO thin film on a conducting substrate can form a dye-sensitized photocathode that can be an active part in a tandem dye-sensitized solar cell (TDSC). To exptl. demonstrate a dye-sensitized nanostructured electrode with a p-type behavior we have chosen nanostructured NiO (deposited on F-doped SnO2). The current-voltage characteristics of 3 different types of sandwich-type solar cells are given (a) the cis-di(thiocyanato)-N,N-bis(2,2'-bipyridyl-4,4'-dicarboxylic acid)ruthenium(II)-coated TiO2 photoanode with a platinized glass as counter electrode, (b) the erythrosin B-coated NiO photocathode with the same counter electrode, and (c) the TDSC with the same photoanode and photocathode.