Improving Charge Transport in Perovskite Solar Cells Using Solvent Additive Technique

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The authors examine the impact of the ACN additive in the film properties of triple cation perovkite films fabricated in ambient condition and the resulting perovskite PV performance. The manuscript originality is questionable, but in general the ambient processing of perovskite film are important for the progress of the perovskite PV technology.  Below you can find some thoughts regarding the manuscript.

1) The title of the manuscript is very general and since the additive engineering has been a common process to improve the perovskite PV, I would suggest the replacement of the title with a more descriptive one.

2) The reference 7 must be corrected

3) The introduction requires more references, generally, but more specific for the solvent additive technique reported in the literature, as well as for the carrier extraction and recombination.

4) In the introduction, there is a duplicate of the current study description.

5)The materials must be mentioned and not just refer to another work as well as the experimental section (e.g. ETL,HTL, the reference solvent, fabrication conditions) must be mentioned at least briefly to improve the readability of the manuscript

6)SEM graphs must have the same bin size for better comparison of the resulted crystal sized. Moreover the statement in line 125

7)"The grains size of the active perovskite films processed with ACN 10% are larger compared to films prepared without using ACN as displayed in the SEM images in the Figure 2" is not clear. In what descriptive quantity they refer to regarding the size (e.g. median, the median ), since the larger crystals inferred from the statistical analysis are at the samle w/o ACN (400 -450nm).

8) In line  127 the statement "most of the film pinholes or defects were suppressed."

But for the 10 % ACN perovskite pin-holes can be distigushed, so the use of the term "suppressed" seems a bit excessive. Moreover, what is the definition of "defects" inferred from the SEM images.

11)In figure 3 the baseline has to be corrected and then be estimated the level of absorption for each additive.

12) in line 190 the statement "Additionally, the XRD results showed a
decrease in the intensity of the PbI2 peak in all cells, with only a small PbI2 peak observed"

The XRD graph have to be adjusted to proper size, so the 001 peak width and position be more clear. Moreover, the PbI2 peak is observed only in the 10% film and not the reference film which has to be discussed in the manuscript. Why the authors believe this occurs and what is the impact on the device performance.

13) The stability graph is better to be presented as relative values for better visual comparison of the results.

Comments on the Quality of English Language

The text has to be reviewed for some grammatical and syntactical corrections.

Author Response

We have attached the file,

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

There are some issues should be solved before it can be accepted for publication.

1. In the introduction, the updated champion PCE of perovskite solar cells is over 26% rather than 25%. This information should be updated and relavent papers should be cited (https://www.nrel.gov/pv/cell-efficiency.html/).  

2. In the Introduction part, for the composition engineering, the paper should be cited (https://onlinelibrary.wiley.com/doi/10.1002/inf2.12256) ; for the interface engineering, the paper should be cited (https://www.sciencedirect.com/science/article/abs/pii/S2211285519304033); 

3. In the Introduction, the authors discussed why the glovebox is needed for the fabrication of PSCs. However, it is previously reported that the perovskite can be made in ambient air and the device showed an efficiency over 18%. The authors need to discussed the work.

4. what is the ETL and HTL used in this work?

5. The fabrication process of perovskite solar cells should be included in the methods part.

6. In figure 5, the label should not be perovskite film control device

7. why all the devices have a very similar degradation rate?

Author Response

We have attached the file

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The author has systematically analyzed the characteristics of perovskite films and solar cells with ACN additives. The study shows that ACN increases the size of perovskite crystals, resulting in improved performance and stability. However, the following issues need to be addressed before publication:

1. Although the author has verified that ACN is also effective in films with triple cation perovskite processed in ambient conditions, similar results have already been reported and summarized in Table 2. While the results are meaningful, achieved in the air with 45% RH at room temperature, Hussein et al. (Journal of Physics and Chemistry of Solids, Volume 149, February 2021, 109792) have previously demonstrated the effectiveness of ACN in ambient processed films. Therefore, the novelty of this work should be highlighted by comparing it with previous studies in the revised version.

2. It is not clear whether the device was encapsulated during the stability test. Additionally, it should be clearly described whether the results are from a storage lifetime test or a light soaking experiment. Please clarify the conditions of the stability test.

Comments on the Quality of English Language

The language of this article is clear and easy to understand. 

Author Response

We have attached the file

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The revised version can be accepted.

Reviewer 3 Report

Comments and Suggestions for Authors

The paper is well-revised.  I recommend publishing this work in the Inorgnics