Ultrahigh open-circuit voltage for high performance mixed-cation perovskite solar cells using acetate anions

Fu, Rui; Zhao, Yicheng; Zhou, Wenke; Li, Qi; Zhao, Yao

doi:10.1039/c8ta04453h

Cited by 18 publications

(11 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As shown in Figure 2, in all of the samples the δ‐phase dominates in the perovskites prior to annealing (0 s). The α to δ phase transition of FAPbI 3 set in after 90 s for the pristine film (Figure 2 A) and was prolonged to 120 s after adding 20 mol % of FAAc (Figure 2 B), which is consistent with the observation in Figure S3 where the change in film color of the FAAc sample occurred later than the that of the pristine film under annealing [16] . Compared to the pristine sample, the FAAc‐modified precursor contains FA + , acetate (Ac − ) and I − simultaneously in the solution.…”

Section: Figuresupporting

confidence: 85%

“…165 °C) than FAI (ca. 260 °C) (Figure S9), [16, 17] the additive tends to evaporate from the film when annealed at 150 °C, and thus the substitution of I − by Ac − in the FAAc‐based film was effectively inhibited during annealing. The process prevented I − anions from evacuating from the perovskite lattice during annealing, alleviating the formation of I vacancies and undercoordinated Pb [11b, 18] .…”

Section: Figurementioning

confidence: 99%

See 1 more Smart Citation

Combined Precursor Engineering and Grain Anchoring Leading to MA‐Free, Phase‐Pure, and Stable α‐Formamidinium Lead Iodide Perovskites for Efficient Solar Cells

Ling

Zhu

et al. 2021

Angewandte Chemie

View full text Add to dashboard Cite

α‐Formamidinium lead iodide (α‐FAPbI3) is one of the most promising candidate materials for high‐efficiency and thermally stable perovskite solar cells (PSCs) owing to its outstanding optoelectrical properties and high thermal stability. However, achieving a stable form of α‐FAPbI3 where both the composition and the phase are pure is very challenging. Herein, we report on a combined strategy of precursor engineering and grain anchoring to successfully prepare methylammonium (MA)‐free and phase‐pure stable α‐FAPbI3 films. The incorporation of volatile FA‐based additives in the precursor solutions completely suppresses the formation of non‐perovskite δ‐FAPbI3 during film crystallization. Grains of the desired α‐phase are anchored together and stabilized when 4‐tert‐butylbenzylammonium iodide is permeated into the α‐FAPbI3 film interior via grain boundaries. This cooperative scheme leads to a significantly increased efficiency close to 21 % for FAPbI3 perovskite solar cells. Moreover, the stabilized PSCs exhibit improved thermal stability and maintained ≈90 % of their initial efficiency after storage at 50 °C for over 1600 hours.

show abstract

Section: Figuresupporting

confidence: 85%

Section: Figurementioning

confidence: 99%

Combined Precursor Engineering and Grain Anchoring Leading to MA‐Free, Phase‐Pure, and Stable α‐Formamidinium Lead Iodide Perovskites for Efficient Solar Cells

Ling

Zhu

et al. 2021

Angewandte Chemie

View full text Add to dashboard Cite

show abstract

“…Cells containing 5% Cs + and/or 5% Rb +39 all exhibit a higher V oc , following the same trend as our modeled results. Although other groups have found higher V oc values up to 1.19 V, 42,43 all V oc values are still smaller than the calculated μ F /e, which implies that deposition of the transport layers results in additional decay pathways and that higher V oc values are feasible by optimizing the transport layers. Interestingly, from our calculations, it is important to note that μ F /e for (MA,FA)Pb(I/Br) 3 is equal to that of the evaporated MAPbI 3 samples (having the same bandgap), implying that both fabrication methods are capable of producing similar quality MHPs.…”

mentioning

confidence: 61%

Comparing the Calculated Fermi Level Splitting with the Open-Circuit Voltage in Various Perovskite Cells

et al. 2019

View full text Add to dashboard Cite

While the power conversion efficiency of metal halide perovskite (MHP) solar cells has increased enormously, the open-circuit voltage, V oc, is still below the conceivable limit. Here, we derive the Fermi level splitting, μF, for various types of noncontacted MHPs, which sets a limit for their achievable V oc, using rate constants and mobilities obtained from time-resolved photoconductivity measurements. Interestingly, we find that for vacuum-evaporated MAPbI3 and K+-doped (MA,FA,Cs)Pb(I/Br)3, the μF/e values are close to the reported V oc values. This implies that for an improvement of the V oc, charge carrier recombination within the bare perovskite has to be reduced. On the other hand, for MHPs with Cs+ and/or Rb+ addition, the experimental V oc is still below μF/e, suggesting that higher voltages are feasible by optimizing the transport layers. The presented approach will help to select which techniques and transport layers are beneficial to improve the efficiency of MHP solar cells.

show abstract

“…In general, alkali metal cation doped PSCs show much higher efficiencies than conventional MAPbI 3 PSCs . More importantly, it is advantageous for device stability to mix some alkali metal cations into the architecture of perovskite crystals, owing to the intrinsic properties of the inorganic component.…”

Section: Stability Challengesmentioning

confidence: 99%

“…Niemann et al investigated the mixedcation perovskite Cs x MA 1-x PbI 3 systematically. [83] They partially replaced the monovalent cations through immersing MAPbI 3 films in the solution of CsI, thus resulting in a continuous uptake of Cs + over time. Using this method, solar cells showed an improvement in cell lifetime from days to a month.…”

Section: Thermal Stabilitymentioning

confidence: 99%

Stability Challenges for Perovskite Solar Cells

Zhou

et al. 2019

ChemNanoMat

Self Cite

View full text Add to dashboard Cite

As energy issues have become prominent, intensive attention has been paid to clean and renewable energy, such as wind energy, tidal energy, geothermal energy and solar energy. Perovskite solar cells, as the third generation of solar cells, possess many advantages, including high power conversion efficiency, simple preparation method and low fabrication cost, etc. Although the power conversion efficiency of this type of photovoltaic device has increased rapidly to more than 23% in less than ten years, stability issues constrain further development. Here, we systematically discuss the degradation mechanism for perovskite materials and their corresponding solar cell devices with a focus on the n‐i‐p structure. Developed strategies for improving device stability are also summarized. We hope this review will provide helpful insights for next stage research on enhancing the state‐of‐the‐art perovskite device stability toward future commercialization.

show abstract

Ultrahigh open-circuit voltage for high performance mixed-cation perovskite solar cells using acetate anions

Abstract: By an FAAc additive-engineering strategy, a high PCE of 21.9% with an ultrahigh VOC of up to 1.19 V was achieved.

Cited by 18 publications

References 38 publications

Combined Precursor Engineering and Grain Anchoring Leading to MA‐Free, Phase‐Pure, and Stable α‐Formamidinium Lead Iodide Perovskites for Efficient Solar Cells

Combined Precursor Engineering and Grain Anchoring Leading to MA‐Free, Phase‐Pure, and Stable α‐Formamidinium Lead Iodide Perovskites for Efficient Solar Cells

Comparing the Calculated Fermi Level Splitting with the Open-Circuit Voltage in Various Perovskite Cells

Stability Challenges for Perovskite Solar Cells

Contact Info

Product

Resources

About