Day 2

1)     A solar cell is a ________

• p-type semiconductor

• n-type semiconductor

• Intrinsic Semiconductor

• p-n junction

The following material cannot be used for solar cell.

• Silicon

• GaAs

• TiO₂

• PbS

The energy in the lead acid battery is stored in the form

• Double Layer

• Nuclear Energy

• Chemical Energy

• Photon Energy

Molecular structure of squaraine dye (SQ) and the UV-vis absorption spectra of SQ in a chloroform solution (black line) and as a 20 nm thick, thin film (red line), spin coated from a SQ solution in chloroform is provided in the image.

Comment on the origin of absorption peak at ~770 nm

• It is due to H-aggregate

• It is due to J-aggregate

• It is due to charge transfer transition

• It is intra-molecular charge transfer transition

UV-vis absorption spectra of carboxylic acid containing squaraine dye, SQ1, in acetonitrile (MeCN) solution (black line) and on TiO₂ surface (red line, TiO₂ film sensitized with SQ1 dye in MeCN) is provided in the image.

Comment on the origin of absorption peak at ~575 nm.

• It is due to H-aggregate

• It is due to J-aggregate

• It is due to charge transfer transition

• It is intra-molecular charge transfer transition

Electrolyte in a dye-sensitized solar cell device (DSSC) helps enhancing the _________ of the device.

• Short-circuit current density

• Fill factor

• Open-circuit voltage

• Charge recombination process

In DSSC device, mesoporous TiO₂ film based photoanode helps in

• Enhancing the charge recombination process

• Decreasing the dye loading

• Increasing the dye loading

• Decreasing the dye-regeneration process

Please select the Li-stuffed garnet

• Li₃PO₄

• Li_0.29La0_.57TiO₃

• Li₇La₃Zr₂O₁₂

• Li_3.957Sr_1.957La_0.043ZrO₆

To reduce the sintering temperature of Li-stuffed garnet, which are kinds of elements suitable for the dopant?

• High melting point

• Low melting point

• Large ionic radii

• Small ionic radii

What is the advantage of LiNi_0.5Co_0.5O₂ as compared with LiCoO₂ as the cathode?

• High voltage

• Low voltage

• Large volume change

• Small volume change