Sequential deposition is demonstrated as an effective technology for preparation of high‐performance perovskite solar cells based on lab‐scale spin coating. However, devices fabricated by scalable methods are lagging far behind their state‐of‐the‐art spin‐coated counterparts, largely due to the difficulty in obtaining high‐quality thin films of perovskites crystallized from printed precursors. Here, a generic strategy that allows sequential deposition of dense and uniform perovskite films via two‐step blade coating is reported. The rational selection of solvent combined with a mild vacuum extraction process enables us to produce uniform lead iodide (PbI2) films over large areas. Significantly, the resulting PbI2 films possess a mesoporous structure that is highly beneficial for the insertion reaction with methylammonium iodide (MAI). It is further identified that the deposition temperature of MAI plays an important role in determining the morphology and crystallinity of the perovskite films. Solar cells using these sequentially bladed perovskite layers yield efficiencies over 16% with high fill factors up to 78%. These results represent important progress toward the large‐scale deposition of perovskite thin films for practical applications. A generic crystallization protocol that allows sequential deposition of dense and uniform perovskite films via two‐step blade coating is reported. The rational selection of solvent combined with a mild vacuum extraction process is deployed to produce uniform PbI2 films over large areas.

Dear Zhang Bowen thank you for asking this interesting question. The fabrication of FAMA perovskite solar cells by the sequential deposition method has been investigated in the following PhD theses:

Moisture Stability of Hybrid Perovskite Solar Cells

https://edoc.ub.uni-muenchen.de/22564/1/Hu_Yinghong.pdf

and

Understanding Film Formation Mechanisms of Sequential Solution-Processed Perovskite for Solar Cell Applications

http://unsworks.unsw.edu.au/fapi/datastream/unsworks:72985/SOURCE02?view=true

Both theses are freely available as public full texts (see attached pdf files).

Unfortunately the first answer to your question has been copied and pasted (without mentioning the source) from the Abstract of a research article which is not available as public full text:

Sequential Deposition of High‐Quality Photovoltaic Perovskite Layers via Scalable Printing Methods

Article Sequential Deposition of High‐Quality Photovoltaic Perovskit...

Perhaps you can access this paper through your institution. Alternatively you can request the full text directly from the authors via RG.

I hope this helps. Good luck with your research and best wishes, Frank Edelmann

Frank T. Edelmann

Dear Mr. Frank T. Edelmann, thank you so much for your informative and valuable answer. I learnt a lot from these references.

There is another question I want to consult you.

When annealing the mix-cation Perovskite layer, many papers report that they anneal it outside glovebox( relative humiditiy is in the range of 20-30%).

I am wondering whether the humidity affected the annealing or not since we usually anneal the Perovskite layer inside glovebox.

However, we find the result of annealing inside is not so good for sequential deposition method.

Could you offer some instruction about annealing for mix-cation devices?

Thank you very much.