Dual-sensitized upconversion-assisted, triple-band absorbing luminescent solar concentrators.

Luminescent solar concentrator-photovoltaic systems (LSC-PV) harvest solar light by using transparent photoluminescent plates, which is expected to be particularly useful for building-integrated PV applications. LSC panels that absorb multiple wavelength bands are required to achieve high power conversion efficiency (PCE). In this study, we demonstrate a pair of downshift LSC and photon upconversion (UC) LSC, absorbing triple bands (violet, green, and red light). The UC is obtained by energy transfer and triplet–triplet annihilation between sensitizer and emitter dyes. In particular, we exploit the dual sensitizer to obtain absorption of the dual wavelength band. The couple with the UC LSC obtains photoluminescence of a single visible wavelength band from the LSC, which enables the use of wide bandgap solar cells to absorb it. Here, we apply mixed-cation perovskite solar cells (PSCs) with high absorption coefficients, especially at visible wavelengths. In our triple-band-absorbing LSC-PSC, we achieve a maximum PCE of 8.99%.