Efficient surface passivation of perovskite films by a post-treatment method with a minimal dose

Kang, Dongho; Kim, Soyeon; Lee, Jin Wook; Park, Nam‐Gyu

doi:10.1039/d0ta10581c

Cited by 69 publications

(64 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The minimized degradation gives space for the defect-healing and re-crystallization process that has been reported to occur in C-PSCs [ 51 , 52 ]. Another explanation for this increase is the suppressed ion migration, which has also been reported in the literature [ 21 ].…”

Section: Resultssupporting

confidence: 58%

“…Among these, phenethylammonium iodide (PEAI) and tetrabutyl ammonium iodide (TBAI) have emerged as highly efficient, achieving PCEs of 23.3%, with Voc of 1.18 V [ 20 ] and 21.6 mA/cm 2 with Voc of 1.12 V respectively [ 21 , 22 ], which is over 90% of the Shockley-Queisser Voc limit. The working mechanism and the role of ammonium iodides, both as additives and as passivation agents, has been widely studied in typical PSCs [ 18 , 19 , 23 , 24 , 25 , 26 , 27 ].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Exploring the Effect of Ammonium Iodide Salts Employed in Multication Perovskite Solar Cells with a Carbon Electrode

et al. 2021

View full text Add to dashboard Cite

Perovskite solar cells that use carbon (C) as a replacement of the typical metal electrodes, which are most commonly employed, have received growing interest over the past years, owing to their low cost, ease of fabrication and high stability under ambient conditions. Even though Power Conversion Efficiencies (PCEs) have increased over the years, there is still room for improvement, in order to compete with metal-based devices, which exceed 25% efficiency. With the scope of increasing the PCE of Carbon based Perovskite Solar Cells (C-PSCs), in this work we have employed a series of ammonium iodides (ammonium iodide, ethylammonium iodide, tetrabutyl ammonium iodide, phenethylammonium iodide and 5-ammonium valeric acid iodide) as additives in the multiple cation-mixed halide perovskite precursor solution. This has led to a significant increase in the PCE of the corresponding devices, by having a positive impact on the photocurrent values obtained, which exhibited an increase exceeding 20%, from 19.8 mA/cm2, for the reference perovskite, to 24 mA/cm2, for the additive-based perovskite. At the same time, the ammonium iodide salts were used in a post-treatment method. By passivating the defects, which provide charge recombination centers, an improved performance of the C-PSCs has been achieved, with enhanced FF values reaching 59%, which is a promising result for C-PSCs, and Voc values up to 850 mV. By combining the results of these parallel investigations, C-PSCs of the triple mesoscopic structure with a PCE exceeding 10% have been achieved, while the in-depth investigation of the effects of ammonium iodides in this PSC structure provide a fruitful insight towards the optimum exploitation of interface and bulk engineering, for high efficiency and stable C-PSCs, with a structure that is favorable for large area applications.

show abstract

Section: Resultssupporting

confidence: 58%

Section: Introductionmentioning

confidence: 99%

Exploring the Effect of Ammonium Iodide Salts Employed in Multication Perovskite Solar Cells with a Carbon Electrode

et al. 2021

View full text Add to dashboard Cite

show abstract

“…[45] The Pb 2+ peaks at 143.2 and 138.3 eV for the control perovskite are shifted to lower binding energy of 142.9 and 138.0 eV by PACl, which is indicative of less undercoordinated Pb 2+ due to effective surface passivation by PACl. [46,47] In addition, no peaks for Pb 0 is obviously observed by the additive. A negligible Cl peak is observed for the PACl case from the Cl 2p XPS (Figure 5b).…”

Section: Resultsmentioning

confidence: 95%

Propylammonium Chloride Additive for Efficient and Stable FAPbI₃ Perovskite Solar Cells

Zhang

Lin

et al. 2021

Advanced Energy Materials

Self Cite

104

120

View full text Add to dashboard Cite

However, the unsatisfied moisture stability of the perovskite materials may become an obstacle for practical applications of PSCs. [5,6] Formamidinium lead iodide (FAPbI 3 ) is a widely used composition for high efficiency PSC owing to its superior properties such as optimal bandgap, high absorption coefficient and long carrier diffusion length, which is better than a prototype perovskite composition of methylammonium lead iodide (MAPbI 3 ). [7][8][9][10][11][12][13] FAPbI 3 has two phases, a nonperovskite heaxagonal phase (δ phase) and cubic perovskite phase (α-phase). [9] Normally, the phase transformation from δ-phase to α-phase FAPbI 3 requires the annealing temperature higher than 120 °C. [14] However, fabricating pure α-FAPbI 3 is a challenging due to the metastable α-FAPbI 3 , where the residual δ-phase forces α-phase to undergo a reverse phase transition back to δ-phase in the room temperature. [15][16][17][18] It has been known that α-phase FAPbI 3 can be stabilized by a partial substitution of FA and/or I with Cs, MA and Rb cation, and Br anion. Nevertheless, stabilizing the pure α-phase FAPbI 3 is crucial for achieving higher efficiency. [15,16,[19][20][21][22][23] Instead of substitution strategy, MACl has been proposed as an additive in perovskite precursor solution for inducing pure α-FAPbI 3 perovskite. It was found that addition of MACl increased crystallinity and grain size as well as formation of the pure black phase perovskite film. [12,24,25] However, an increase of bandgap cannot be excluded due to a potential incorporation of To achieve high efficiency perovskite solar cells (PSCs) based on α-phase formamidinium lead iodide (FAPbI 3 ), addition of methylammonium chloride (MACl) in the precursor solution is commonly used, mainly because of phase stability and improvement of grain size and crystallinity. However, the instability of MA in the perovskite limits the device long-term stability. In this report, n-propylammonium chloride (PACl) is proposed as an alternative to MACl for more stable and efficient FAPbI 3 -based PSCs. Perovskite grain size is increased after addition of PACl. Unlike the MA cation, the propylammonium cation passivates the grain boundary rather than being incorporated into the perovskite lattice due to larger ionic size, which minimizes the change in bandgap. Carrier lifetime is significantly increased by more than five times from 405 to 2110 ns with the PACl additive with negligible trap-mediated recombination, while only four times longer carrier lifetime is observed by MACl additive. As a result, a power conversion efficiency over 22.2% is achieved by 20 mol% PACl additive, which is one of the best efficiencies among the MA-free and Br-free PSCs. In addition, stability against moisture is much better for PACl than for MACl due to an in situ formed barrier at the bulk perovskite.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/aenm.202102538.

show abstract

“…TBA + has been reported to assist crystallization and film formation to improve photovoltaic performance and act as hydrophobic materials to promote stability with formation of lowdimensional materials when used as additives, [43][44][45][46][47] and most recently, as post-treatment materials [48,49] during the submission of this paper. Inspired by these results, it is possible to form [TBA]PbI 3 haloplumbate on the surface of perovskite with TBAI treatment.…”

Section: Introductionmentioning

confidence: 99%

Water Stable Haloplumbate Modulation for Efficient and Stable Hybrid Perovskite Photovoltaics

Wang

Zhang

Milić

et al. 2021

Advanced Energy Materials

View full text Add to dashboard Cite

the result of multiple factors, such as the reactivity to moisture, oxygen, thermal stress, voltage bias, and light, which cause the unexpected degradation of PSCs. [16][17][18] In recent years, among all the methods for improving the stability of PSCs, [19,20] interfacial engineering of thin interlayers on the surface of the perovskite layer is proved to be one of the most effective methods. [21,22] This has involved various molecular assemblies [23][24][25][26] as well as graphene composites, [27] along with lowdimensional perovskites, [28,29] polymers, [30] and inorganic materials. [31] An ideal interfacial modulator should fulfill several requirements, namely: (i) forming a well-defined compact structure with good coverage, (ii) featuring excellent stability against environmental and operational conditions, with (iii) appropriate energy alignment, along with the (iv) passivation capacity. A compact and well-covered interlayer can prevent water and oxygen from damaging the perovskite layer underneath, while preventing the volatile species from being released, whereas the interlayer itself should be stable against moisture, oxygen, thermal, and other operating factors to provide long-term protection. Finally, the interlayer should ideally have a good energy level alignment, so that it would not limit the charge carrier transport, while it should also be able to passivate defects on the surface of the perovskite The commercialization of perovskite solar cells is mainly limited by their operational stability. Interlayer modification by thin interface materials between the perovskite and the charge transport layers is one of the most effective methods to promote the efficiency and stability of perovskite devices. However, the commonly used interlayer materials do not fulfill all the demands, including good film quality, excellent stability, and passivation capability without interfering with the charge transport. In this work, a water stable haloplumbate [TBA]PbI 3 for interfacial modification that meets these demands is proposed, which is formed on the perovskite surface in situ by tetra-butylammonium iodide treatment. Benefiting from its passivation effect and robustness, the modified devices result in a power conversion efficiency of 22.90% with enhanced environmental and operational stability. In addition, the self-limiting effect of the reaction contributes to the controllability of device fabrication and the repeatability of device performance.

show abstract

Efficient surface passivation of perovskite films by a post-treatment method with a minimal dose

Abstract: Post-treatement of an unannealed perovskite film is found to be more efficienct way to passivate defects of perovskite solar cells.

Cited by 69 publications

References 54 publications

Exploring the Effect of Ammonium Iodide Salts Employed in Multication Perovskite Solar Cells with a Carbon Electrode

Exploring the Effect of Ammonium Iodide Salts Employed in Multication Perovskite Solar Cells with a Carbon Electrode

Propylammonium Chloride Additive for Efficient and Stable FAPbI₃ Perovskite Solar Cells

Water Stable Haloplumbate Modulation for Efficient and Stable Hybrid Perovskite Photovoltaics

Contact Info

Product

Resources

About

Efficient surface passivation of perovskite films by a post-treatment method with a minimal dose

Abstract: Post-treatement of an unannealed perovskite film is found to be more efficienct way to passivate defects of perovskite solar cells.

Cited by 69 publications

References 54 publications

Exploring the Effect of Ammonium Iodide Salts Employed in Multication Perovskite Solar Cells with a Carbon Electrode

Exploring the Effect of Ammonium Iodide Salts Employed in Multication Perovskite Solar Cells with a Carbon Electrode

Propylammonium Chloride Additive for Efficient and Stable FAPbI3 Perovskite Solar Cells

Water Stable Haloplumbate Modulation for Efficient and Stable Hybrid Perovskite Photovoltaics

Contact Info

Product

Resources

About

Propylammonium Chloride Additive for Efficient and Stable FAPbI₃ Perovskite Solar Cells