Hysteresis analysis in dye-sensitized solar cells based on external bias field effects

The current density-voltage (J-V) hysteresis phenomenon occurs in perovskite solar cells as well as dye sensitized solar cells (DSCs); however, it has received little attention in DSCs. We consider that the trapping detrapping-induced variation of the charge collection efficiency might cause J-V hysteresis. Therefore, we conduct a systematic study on the influence of an external bias field during and before) V measurements in typical DSCs. We find that the J-V performance of DSCs significantly depends on the scan bias direction and the external bias field before and during measurements. Our results indicate that the external-bias-field-modulated charge injection, trapping detrapping, and accumulation processes in DSCs are possible causes for the anomalous J-V behavior. (C) 2017 Elsevier B.V. All rights reserved.