Performance enhancement of polymer solar cells by incorporating Ag nanoparticles at an indium tin oxide/MoO3 buffer layer interface

In the present study, the plasmonic effects of silver nanoparticles (Ag NPs) have been utilized to improve the performance of polymer solar cells. Plasmonic polymer solar cells were fabricated by incorporating Ag NPs at the indium tin oxide (ITO)/MoO3 buffer layer interface. The size of the Ag NPs has been optimized to improve the device performance. The optimized device with 75 nm sized Ag NPs shows 26% enhancement in the power conversion efficiency (PCE) compared with the reference device. The short circuit current density mainly contributes to the efficiency enhancement compared with other device parameters. The diffuse reflectance measurements indicate that there is significant enhancement in the optical absorption of active layers when Ag NPs are incorporated into the devices. The scattering cross section of Ag NPs and electric field intensity distribution around the nanoparticles were modeled by finite-difference-time-domain simulations. The experimental results and theoretical simulations revealed that both far-field scattering and near-field concentration of light contributed significantly to the PCE enhancement of the devices.