Gratzel cell

Figure 14.7. Left Solution-processed quantum dot structure of InP nanoparticles (black dots) in a Ti02 nanoparticle array (open circles). The QDs could sensitize an optical response similar to the dye in a Gratzel cell. Right A schematic of very small QDs (balls) bonded to a controlling surfactant that is bonded to a surface specific element, such as a TCO surface.

In dye sensitized solar cells (or Gratzel cells [180, 181]), a redox mediator is required to allow charges to be transported from the mesoporous and light sensitive Ti02 film to the cathode. Although other systems have been studied, the equilibrium potential, mobility, and stability of the h j system are most suitable for this application and most cells developed to date employ the iodine redox system in an organic solvent environment. 

The new DSSC developed by Gratzel and co-workers, the so-called Gratzel cell, has very attractive characteristics as follows ... 

The Gratzel cell is composed of a Ru dye attached to a porous Ti02 film of about 10 xm thickness on conducting glass (photoelectrode), an electrolyte solution, a spacer in between two electrodes, a Pt-sputtered conducting glass (counter elec-... 

Figure 1 Schematic structure of dye-sensitized nanocrystalline Ti02 solar cell, Gratzel cell. (From Ref. 12.)...

Alternate concepts to thin films, such as dye-sensitized solar cells, also known as Gratzel cells, are being explored... 

Similarly, the search for a stable dye material and better electrolyte material in dye-sensitized cells (Gratzel cells) has a potential to lead to lower-cost solar cells. There is a need to increase the stable efficiency of such cells a stable efficiency of about 10 percent could be quite useful. 

Gratzel Cell with an Ionic Liquid Based on Iodide... 

Gratzel Cell Containing a Low Viscous Ionic Liquid... 

Figure 15.6 shows the relationship between Jsc of the Gratzel cell and the viscosity of various liquid media under the same conditions [21]. The Jsc of the DSSC system depends simply on the viscosity of the liquid media. However, as described above, the Jsc of iodide-based RTILs is much higher even where viscosity is higher than 200 mPas at 25°C. As shown in the figure, the amount of iodine (I2) affects the improvement in Jsc- This implies that the diffusion coefficient of the iodide... 

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