EFFECT OF AMBIENT AIR CONDITIONS ON LOW FREQUENCY NEGATIVE CAPACITANCE OF NC-TIO₂/P3HT HETEROJUNCTION SOLAR CELLS

Abstract

We report the negative capacitance of nanocrystalline titanium dioxide/poly (3-hexyl thiophene), nc-TiO 2 /P3HT, heterojunction solar cells. In air, low frequency negative capacitance has been observed under forward bias associated with high values of conductance. Interestingly, the negative capacitance disappear when the device was placed in vacuum chamber. These results are attributed to affect the ambient conditions on the charge carrier concentration in materials used to fabricated solar cells and increase the bulk region resistance.

Study the Effect of Ruthenium Dye Layer on Negative Capacitance in Solar Cells Based on the Nc-TiO<sub>2</sub> Semiconducting Polymer Heterojunction

“…Under illumination long lived photogenerated charges at the P3HT:PCBM interfaces increase electron-hole bimolecular recombination rate, which in turn renders the capacitance less negative. In our recent report [6], the negative capacitance of P3HT/nc-TiO 2 shows a dependence of the presence of air around the device. Under vacuum the negative capacitance gradually disappears with increasing the pressure in vacuum chamber.…”