Colored Silicon Heterojunction Solar Cells Exceeding 23.5% Efficiency Enabled by Luminescent Down-Shift Quantum Dots.

Colored solar panels, realized by depositing various reflection layers or structures, are emerging as power sources for building with visual aesthetics. However, these panels suffer from reduced photocurrent generation due to the less efficient light harvesting from visible light reflection and degraded power conversion efficiency (PCE). Here, color-patterned silicon heterojunction solar cells were achieved by incorporating luminescent quantum dots (QDs) with high quantum yields as light converters to realize an asthenic appearance with high PCE. We found that large bandgap (blue) QD layers can convert ultraviolet light into visible light, which can notably alleviate the parasitic absorption by the front indium tin oxide and doped amorphous silicon. Additionally, a universal optical path model was proposed to understand the light transmission process, which is suitable for luminescent down-shift (LDS) devices. In this study, solar cells with a PCE exceeding 23.5% were achieved using the combination of a blue QD layer and a top low refractive index anti-reflection layer; the obtained PCE was the highest for a color-patterned solar cell. Our results suggest an enhanced strategy involving incorporation of luminescent QDs with an optical path design for high-performance photovoltaic panels with visual aesthetics. This article is protected by copyright. All rights reserved.