Nanoscale color control of perovskite solar cells using Fano resonances of aluminum arsenide nanoarrays

Colorful perovskite solar cells have been widely explored in building-integrated photovoltaics for esthetic requirements. However, a principle to control both light reflection peak wavelengths and widths on the nanoscale has not been carried out, which is critical to realize pure colors controllably, thus impeding large-scale application severely. In this paper, we presented a simulation pathway for the nanoscale color control through Fano resonances interaction in aluminum arsenide nanocylinder clusters, which are embedded in the glass above indium tin oxide layers of perovskite solar cells. The Fano resonances are controlled through the adjustment of periods, diameters, and heights of the aluminum arsenide nanocylinder clusters, and thus, the solar cells exhibit extremely narrow reflection peaks. The full widths at half-maximum are measured from 8 to 15 nm, and the tuning resolution of the reflection peak position can reach 1 nm only through the adjustment of the nanocylinder heights. Compared to a blank solar cell, slight optical absorption reductions of 3.41%, 6.31%, and 6.43% are demonstrated in blue, green, and red colored Fano structure integrated perovskite solar cells, respectively. We have also verified that the solar cell’s colors are independent of the incident light angles, satisfying the requirement of building decoration. The results pave a promising strategy with the potential applicability of colorful perovskite solar cells in building-integrated photovoltaics.