P4814 Optical and electronic property tailoring by MoS2-polymer hybrid solar cell
Arul varman Kesavana, Arun D Raoa, Praveen C Ramamurthya
918022932627, Department of Materials Engineering, Indian Institute of Science, Bangalore, 560012, IN
The ternary blend system such as binary donor and an acceptor or binary acceptor and a donor offers a way to improve the power conversion efficiency of the polymer solar cells (PSCs) by enhancing optical properties or electrical properties. In this work, PTB7, PC71BM and Molybdenum disulfide nano-sheet (MoS2NS) ternary blend system were investigated as an active layer for OPV. The optimized ternary blend system showed highest power conversion efficiency of 8.18 %. The incorporation of MoS2NS in the PTB7:PC71BM binary system showed increased PCE from 6.98 % to 8.18 %, which is an increment of 17%. The origin of improved PCE mainly arises from the significant increment in JSC and marginal change in VOC and FF. This improved power conversion efficiency (PCE) should be due to increased light harvesting and improved charge carrier mobility in the active layer. The marginal enhancement in VOC and FF was correlated with the density of trap states (DOS) obtained from capacitance measurement of the device. The optical absorption and energy transfer mechanism of the ternary blend film is explained by absorption and photoluminescence measurement respectively. Further, the conversion efficiency due to improved charge carrier transport was described by modified SCLC mobility measurements for electron and hole only devices. The obtained result shows that presence of MoS2NS along with PTB7:PC71BM binary system play dual role like an improved charge transport layer as well as light harvesting.