Improved Quantum Efficiency by Advanced Light Management in Nanotextured Solution-Processed Perovskite Solar Cells

Rémi Colom,Steve Albrecht,Klaus Jäger,Amran Al-Ashouri,Philipp Tockhorn,Lukas Kegelmann,Thomas Unold,Johannes Sutter,Sven Burger,Christiane Becker,Marcel Roß

doi:10.1021/acsphotonics.0c00935

Abstract

Light management strategies can increase the efficiency of perovskite single-junction and tandem solar cells. In this study, we present perovskite solar cells deposited on different shallow nanotextures by spin-coating. A morphological and optoelectronic analysis demonstrates a high quality of the perovskite absorber, regardless of the substrate. Using both, a nanotexture and a sodium fluoride antireflective coating, enables us to improve the power conversion efficiency by 1.0%abs to 19.7%, when compared to its planar reference. A characterization of the optical performance of nanotextured perovskite solar cells and rigorous optical simulations reveal that the gain in efficiency can be largely attributed to reduced reflection losses and therefore increased absorption in the perovskite. Our nanotextured perovskite solar cells reach 93.6% of the attainable current density, marking the highest reported value for perovskite single-junctions and approaching those of established photovoltaic technologies. Our results demonstrate that nanotextures can be applied to solution-processed perovskite solar cells and pave the way to increased power conversion efficiencies by light management not only in perovskite single-junction but also perovskite–silicon tandem solar cells.

Highlights

Light management strategies can increase the efficiency of perovskite single-junction and tandem solar cells
The solar cell consists of the following layers: First, indium tin oxide (ITO) as a transparent conductive oxide (TCO) is sputtered on the glass substrates covered with nanoimprinted resist layers
Figure S9), we adjust the current density to external quantum efficiency (EQE)-integrated JSC values, as displayed in Figure 3b

Summary

■ RESULTS

We investigate the growth of spin-coated perovskite layers on different textures, with texture heights ranging from about 220 to 600 nm. Together with the morphological analysis with SEM, AFM, and XRD measurements, these results confirm that the perovskite quality is comparable on the planar and the nanotextured substrates This is in contrast to other thin-film solar cell materials, such as amorphous or crystalline silicon, which often must balance a trade-off between optical and electronic performance when using a textured substrate.[62−64]

■ SOLAR CELL RESULTS

■ CONCLUSION

■ ACKNOWLEDGMENTS

■ REFERENCES