A new approach to optimize the active layers of photovoltaic devices using area under the curve of absorption profile

摘要

Optimization of photovoltaic (PV) active layers is usually carried out in terms of the energy bandgap (E-g) variation of the bulk heterojunction (BHJ) layers. However, the non-monotonic change in the E-g does not guarantee the achievement of a maximum absorption capability at the optimum condition, despite the broadened absorption spectrum. Hence, alternative strategies need to be researched in order to assign the best possible condition at which the active layer can convert the highest possible number of exposed photons to free electrons when it is employed in PV devices. Therefore, in this work, we propose a new approach that can be effectively used to optimize the BHJ active layers in terms of photon to electron conversion, considering the absorption profile of the system. Herein, the area under the curve (AUC) of the absorption profile is utilized to optimize the active layers of photovoltaic devices. A ternary system based on P(TRI-co-TER):Beetroot dye:PINDOLE was investigated and analyzed to formulate the proposed technique. Results showed that a linear correlation was produced between the AUC and photocurrent density (J(ph)), which can be ultimately used to optimize the active layers of PV devices.