The dual localized surface plasmonic effects of gold nanodots and gold nanoparticles enhance the performance of bulk heterojunction polymer solar cells

Abstract

In this study, we investigated the effects of plasmonic resonances induced by gold nanodots (Au NDs), thermally deposited on the active layer, and octahedral gold nanoparticles (Au NPs), incorporated within the hole transport layer, on the performance of bulk heterojunction polymer solar cells (PSCs) based on poly(3-hexyl thiophene) (P3HT) and [6,6]-phenyl-C61butyric acid methyl ester (PC61BM). Thermal deposition of 5.3-nm Au NDs between the active layer and the cathode in a P3HT:PC61BM device resulted in the power conversion efficiency (PCE) of 4.6%—that is 15% greater than that (4.0%) for the P3HT:PC61BM device without Au NDs. The Au NDs provided near-field enhancement through excitation of the localized surface plasmon resonance (LSPR), thereby enhancing the degree of light absorption.In addition to the thermally deposited Au-NDs, embedding Au NPs within the poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) to form a dual metallic nanostructure can further enhance PCE to 4.8%—that is about 20% greater than that of the conventional P3HT:PC61BM cell. Thus, Au NPs and Au NDs appear to have great potential for the application in high-efficiency LSPR-enhanced PSCs.