Optical/electrical integrated design of core-shell aluminum-based plasmonic nanostructures for record-breaking efficiency enhancements in photovoltaic devices

Recently plasmonics has gained tremendous interest in solar cell research because it is capable of improving sunlight-conversion efficiencies. However, plasmonic photovoltaic nanostructures with both excellent optical properties and high electrical conductivities have not been developed, thus limiting the efficiency breakthrough. In this paper, we present an optical/electrical integrated design for plasmonic photovoltaic nanostructures by synthesizing core-shell nanomaterials: Aluminum-coated copper nanoparticles. A copper nanocore was synthesized by chemical methods, and then an aluminum nanoshell was physically deposited on the nanocore surface. Strong light-scattering properties have been demonstrated due to the controllable morphology of the nanoparticles and the UV plasmon response of the aluminum nanoshells. Ultrahigh electrical conductivities have been achieved by the pure metallic nanoshells. Once the aluminum-based core-shell particles were integrated into high-efficiency amorphous silicon solar cells, we demonstrated a tremendous efficiency enhancement of 15.4%, which is 51% higher than that from the state-of-The-Art plasmonic technique using silver nanostructures.