Abstract

Recently, inorganic and hybrid light absorbers such
as quantum dots and organometal halide perovskites have been
studied and applied in fabricating thin-film photovoltaic devices
because of their low-cost and potential for high efficiency. Further
boosting the performance of solution processed thin-film solar
cells without detrimentally increasing the complexity of the device
architecture is critically important for commercialization. Here, we
demonstrate photocurrent and efficiency enhancement in mesosuperstructured
organometal halide perovskite solar cells incorporating
core−shell Au@SiO2 nanoparticles (NPs) delivering a
device efficiency of up to 11.4%. We attribute the origin of
enhanced photocurrent to a previously unobserved and
unexpected mechanism of reduced exciton binding energy with the incorporation of the metal nanoparticles, rather than
enhanced light absorption. Our findings represent a new aspect and lever for the application of metal nanoparticles in
photovoltaics and could lead to facile tuning of exciton binding energies in perovskite semiconductors.