Highly Efficient Monolithic Perovskite/Perovskite/Silicon Triple‐Junction Solar Cells

Abstract

Wide‐bandgap metal halide perovskites have demonstrated promise in multi‐junction photovoltaic (PV) cells. However, photoinduced phase segregation and the resultant low open‐circuit voltage (Voc) have greatly limited the PV performance of perovskite‐based multi‐junction devices. Here, we report a alloying strategy to achieve uniform distribution of triple cations and halides in wide‐bandgap perovskites by doping Rb+ and Cl− with small ionic radii, which effectively suppresses halide phase segregation while promoting the homogenization of surface potential. Based on this strategy, a Voc of 1.33 V was obtained from single‐junction perovskite solar cells, and a VOC approaching 3.0 V and a power conversion efficiency (PCE) of 25.0% (obtained from reverse scan direction, certified efficiency: 24.19%) on an 1.04‐cm2 photoactive area could be achieved in a perovskite/perovskite/c‐Si triple‐junction tandem cell, where the certification efficiency and stabilized power output (SPO) are by far the greatest PV performance of perovskite‐based triple‐junction tandem solar cells. This work overcomes the performance deadlock of perovskite‐based triple‐junction tandem cells by setting a materials‐by‐design paradigm.This article is protected by copyright. All rights reserved

Manipulating Wide-Band-Gap Perovskite Compositions via Br Sources for Highly Efficient Perovskite/Silicon Tandem Solar Cells

“…The FABr film exhibited a significantly longer τ ave of 966.2 ns compared to the MABr film (107.6 ns) and the PbBr 2 film (248.5 ns). This indicates a marked reduction in nonradiative recombination processes within the FABr film. , Figure g–i presents confocal PL mapping images of perovskite films derived from various bromide sources. Darker regions within these PL maps correspond to higher trap densities .…”

“…This indicates a marked reduction in nonradiative recombination processes within the FABr film. 51,52 Figure 2g−i presents confocal PL mapping images of perovskite films derived from various bromide sources. Darker regions within these PL maps correspond to higher trap densities.…”

Thermal degradation in methylammonium–formamidinium–guanidinium lead iodide perovskites

“…Nevertheless, despite the greater focus of the current literature on FA + -based perovskite solar cells, the top efficiency solar cells today still contain the less stable MA + cations. 54,55 Considering this scenario, in the present work we used a combination of different experimental techniques, including X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and mass spectrometry-coupled thermogravimetry analysis, to systematically investigate the degradation conditions with time and temperature considering a robust set of compositions of the GA x FA y MA 1− x − y PbI 3 system. The results show that mixed-cation halide perovskites generally exhibit higher thermal stability with lower degradation rate constants.…”

Inhibiting perovskite decomposition by a creeper-inspired strategy enables efficient and stable perovskite solar cells

“…In addition, the non-stoichiometry, and composition segregation of the perovskite can also determine their long-term stability 18 – 20 . For example, the mixed halide perovskite film shows huge potential in fabricating efficient perovskite tandem solar cells, however, the halide segregation severely impacts the film stability 21 . Except from the perspective of halide anion, cation such as MA + and FA + also brings difficulty in fabricating perovskite film with excellent stability, since the MA + and FA + can be decreased through migration or evaporation under moisture or thermal environment, resulting in the composition segregation and film decomposition 22 – 24 .…”