Efficiency Optimization on Dye-Sensitized Solar Cells With Low-Frequency Noise Analysis

The effects of time durations for ZnO nanorod growth and dye loading on a ZnO-based dye-sensitized solar cell's efficiency and 1/f low-frequency noise (LFN) spectral were analyzed. Sufficient time durations for ZnO growth and dye loading were required for achieving optimum photoconversion efficiency. Extending these two time parameters beyond the optimal, however, reduced the efficiency due to nanorod defects and dye agglomerations. The mechanisms inducing the change in the efficiency was reflected in the LFN spectral and explained on the basis of Kleinpenning's noise equation and excessive noises in the presence of structural defects.