Hybrid Core‐Shell Plasmonic Nano‐Particles for Effective Collection of Photocurrent

Optical absorption is a key factor governing the performance of bulk‐heterojunction polymer solar cells (PSC). In this study, hybrid plasmonic nanoparticles (NPs) are employed to mitigate the trade‐off between enhanced light absorption and charge recombination in PSC. Double core‐shell plasmonic NPs composed of zinc, copper, and silver (Zn@Cu@Ag) were successfully synthesized via a wet‐chemistry process and followed by integration of NPs into the solar absorber layers, at varying concentrations. Solar cells are fabricated from polymers blend active layer composed of poly(3‐hexylthiophene) (P3HT) as a donor and phenyl‐C60‐butyric acid methyl ester (PCBM) as an acceptor. The experimental data suggest that the devices fabricated with plasmonic NPs exhibited a 35% enhancement in power conversion efficiency, at optimum concentration, compared to the reference cells. This improvement is attributed to enhanced optical absorption and suppressed charge recombination in PSC due to the synergistic effect of local surface plasmon resonance (LSPR) and far‐field light scattering. This is evident by the measured high photo‐currents and enhanced device performances. More discussions are provided in the following chapters.