Determination of the electron lifetime in nanocrystalline dye solar cells by open-circuit voltage decay measurements.

Recently, a new class of photoelectrochemical cells based on nanoscaled porous metal oxide semiconductors (dye-sensitized solar cell) has promoted intense research due to the prospects of cheap and efficient conversion of visible light into electricity and of new applications such as transparent solar cells. It is widely agreed that the electron-transfer kinetics play a major role in determining the energy conversion efficiency of dye-sensitized solar cells. 3] Herein, we develop a new powerful tool to study the electron lifetime in dye solar cells as a function of the photovoltage (Voc) ; the open-circuit voltage-decay (OCVD) technique. This technique has certain advantages over frequenIn summary, the temperature effect on the arrangement of stilbenoid dendrimers on HOPG is presented in this work. It is seen that SD12 molecules form well-ordered hexagonal nanostructures at 16 C. However, if the adlayer is annealed at 65 C, the adlayer structure is changed into a well-ordered parallelogram nanostructure in a close-packed arrangement with a higher surface coverage. The phenomenon described here supports the earlier reports on two liquid-crystalline phases for SD12. The results in this research are useful in understanding the phase transition of SD12 as well as metastable complex systems with temperature.

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