Internal Analysis and Parameter Optimization of Bilayer Organic Solar Cell

In this research paper, a bilayer heterojunction organic photovoltaic cell consisting Poly (3‐hexylthiophene) (P3HT) and Fullerene derivative [6,6]‐Phenyl C61 butyric acid methyl ester (PCBM) is modelled and analyzed. The device physics is investigated through internal vertical cut‐line analysis followed by a systematic variation of the donor and acceptor layer thickness to study the resulting variations in performance parameters independently. The variation in the donor layer thickness from 0.01 to 0.07 µm showed the current density to vary with maximum at 4.0 mA/cm 2 at 0.04 µm similarly for acceptor layer maximum was attained as 3.8 mA/cm 2 at 0.05 µm thickness. The obtained results reveal the notable significance of donor acceptor interface in performance of bilayer photovoltaic cell via displaying the arrangement of field and current at the interface. The results further confirm that photovoltaic performance of a bilayer solar cell is strongly dependent on the thickness of both the donor and acceptor layers. Most importantly the obtained results also verify that the concept of increasing thickness to enhance performance parameters is counterintuitive as larger thickness leads to significant recombination and thickness can only be increased as far as the transit time of carriers is maintained.