Modification of Solar Energy Harvesting in Photovoltaic Materials by Plasmonic Nanospheres: New Absorption Bands in Perovskite Composite Film

摘要

Thin-film perovskite-based photovoltaics has great potential to make an important contribution to the ongoing search for new sources of clean renewable energy. Excitation of localized surface plasmons in metal nanoparticles could establish a new route for an improvement of the performance of such devices. Using the tools of electrodynamics (Lorenz-Mie theory adopted for absorbing host media), we predict a strong red shift in the spectral activity of gold and silver nanospheres and modification (negative or positive) of white and solar light harvesting in the film of perovskite host caused by centrally distributed plasmonic nanospheres. The enhancement of absorption in perovskite host is proven to be possible for photons with energies close to or smaller than the energy band gap in perovskite, with the final effect depending on the diameter of nanospheres, their concentration, and kind of metal. From the electronic band structure point of view, the predicted strengthening of absorption can be interpreted as the effect of semiconductor doping with metals resulting in increased photocurrent. New allowed energy bands within the band gap of the undoped perovskite semiconductor allow explaining the recently observed effect of boosted photocurrent generation