▎ 摘 要
We demonstrate power conversion efficiency improvement in polymer solar cells (PSCs) through incorporating gold nanoparticles with graphene shell (Au NPs@Gr), positioned between hole transport and active layers. Au NPs@Gr improves roughness and can penetrate to active layer, enhance optical absorption and induce more balanced charge transfer. Band gap of the donor was analyzed by Tauc's formula which showed band gap decline in Au@Gr-based solar cells (1.89 eV). Life time, recombination rate and bulk resistance were analyzed by impedance spectroscopy. Graphene shell over Au NPs incorporates in charge transport and the life time of the charges improved 80% when charge recombination resistance increased from 2.08 to 2.37 K Omega. Solar cell photovoltaic parameters also showed higher short circuit current (42%) and higher power conversion efficiency (100%) in comparison to reference. Results indicated that Au NPs@Gr structure can be considered as an effective material for high performance PSCs and future high-tech applications.