Light-Induced Photoluminescence Quenching and Degradation in Quasi 2D Perovskites Film of (C₆H₅C₂H₄NH₃)₂ (CH₃NH₃)₂[Pb₃I₁₀]

Round 1

Reviewer 1 Report

 In this report, the authors have investigated the light-induced PL quenching and degradation of quasi 2D perovskites of PEA2MA2Pb3I10.  It is observed that efficient encapsulation and appropriate long-pass filter could be very useful to enhance the lifetime of devices. The experiment has been carried out systematically.

This work is interesting for the researcher working in HaPSCs. It can be considered for publication after addressing the following comments.

Comments:

1. It is suggested to include an SEM image of the film in supporting information. If possible please, confirm the Pb:I composition ratio.
2. In Fig. 1 b, c, d (inset), it is suggested to evaluate at the FWHM. Does it correlate with the intensity and the carrier accumulation?
3. Although the authors have mentioned the degradation, they have not discussed the optoelectronic aspect of degradation. Please include this aspect in the introduction；https://www.mdpi.com/2079-4991/9/8/1120　　and https://pubs.rsc.org/en/content/articlelanding/2018/tc/c7tc03733c#!divAbstract　
4. In line 131, it has mentioned that... Thus here PEA2MA2Pb3I10 was subjected to irreversible chemical decomposition., Can it be discussed in detail with an illustration.  
5. Since a working device is tested under electric bias. Did the author ever test the electro-luminescence? It is recommended to evaluate the PL and EL. For your reference, the references below have discussed the EL spectra in 2D and 3D HaPSCs.; https://aip.scitation.org/doi/10.1063/1.4964413 ; https://pubs.rsc.org/en/content/articlelanding/2017/TC/C7TC02822A#!divAbstract

Author Response

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Reviewer 2 Report

The manuscript entitled “Light Induced Photoluminescence Quenching and Degradation  in Quasi 2D Perovskites Film of (C6H5C2H4NH3)2 (CH3NH3)2[Pb3I10] ” by Sheng at al. describe some Photoluminescence quenching studies on a Quasi 2D Perovskite. The study is interesteing although rather simple, and some aspects need to  be significantly improved prior to be published in Applied Sciences.

One of these aspects is the English language, which must be fully reviewed. Likewise, some typos and mistakes must be also corrected, as the following ones:

 

L10 perovskitess and along the text. Correct to perovskite or perovskites (in context).

 multiphase of n = 1, 2, 3 in PEA2MA2Pb3I10 is not clear to reader , what is n, the number of layers? This cannot be understood with the information provided? Regrettably, this also occurs in the discussion. (L 155 which is assigned to the n = 1 material of the 2D perovskites, namely, PEA2PbI4 (see Figure S3c) [37]. Some explanation is needed about the multiphase structure, and even for the own compound. Despite being a well-known material, some explanation is needed for a better understanding, especially for readers not familiarized with the area.

Keywords: Two dimensional perovskites; PEA2MA2Pb3I10; Photostability; PL quenching; Degradation processesIntroduction. Delete introduction and write photoluminescence. In addition, the very first time that Photoluminescence is cited in the text (L31, or in the abstract) the whole word should appear instead of PL.

 

(PEA=C6H5(CH2)2NH3),  MA=CH₃NH₃,  BA = CH3(CH2)3NH3,..   all these ligands are cationic ammonium derivatives, so their positive charge should be explicitly indicated.

 

L57-59 different sizes are used. The same also occurs in the conclusions.

N,N-dimethylformamide, N,N- must appear in italics

L92 its PL intensity after laser beam being unblocked recovers to its original level and then decreases as previous circle. Is it a cycle? The whole sentence is not clear.

Figures 1 and 3 are of low quality, and the footnotes are also unclear. The numbers and magnitudes of scales appear to be too big or bold for the insets.

Correlation in fig 4a and 4b on right side is not clear, even when amplified on right side. This figure should be improved.

Author Response

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Reviewer 3 Report

In this work, light-induced photoluminescence quenching as well as degradation of quasi 2D perovskites (namely, PEA2MA2Pb3I10 (PEA=C6H5(CH2)2NH3, MA=CH3NH3)) was investigated using steady-state PL spectroscopy and complementary characterization including XRD and absorption spectroscopies). It was demonstrated that light-induced PL quenching occurred with different dynamics, depending on the wavelength and intensity of laser as well as film’s environment. Higher laser intensity and/or higher photon energy resulted in faster decomposition of the perovskite. Exclusion of oxygen suppressed light-induced PL quenching and film degradation.

The manuscript is nicely written and provides new knowledge on the phostability of 2D perovskites. This is clearly a subject which is worthy of investigation and has been less worked on compared to more conventional perovskites. However, some further information on the PL decay and the film microstructure would assist in obtaining a more clear picture with regard to the investigated 2D perovskite photostability in various environments and under different excitation conditions ( laser wavelength and power) and strengthen the manuscript. Thus, I recommend that the manuscript can be accepted pending some revisions with regard to the following comments.

1. Information on the kinetics of PL decay in the various environments as well as with different excitation conditions is missing. This information would certainly add information on the time scale of the exciton decay and the mechanisms likely associated with this process.

2. SEM measurements might be useful to investigate in more detail the film microstructure and composition and correlate it with the observed changes and the associated discussion.  

 

Author Response

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Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The authors have been revised addressing the reviewer's comments. 

It is recommended to accept for publication. 

Cheers

 

Reviewer 2 Report

Authors have satisfactorily corrected most of the problems related to the text, and some figures have been properly improved.

Reviewer 3 Report

The authors have revised the manuscript, taking into careful consideration the reviewers' comments, and made out the essential changes to improve the manuscript's quality and validate their conclusions. Thus, the manuscript can now be accepted in its current, revised, version.