Dear friend Devendra R B

Annealing CZTS deposited on Molybdenum can be tricky and requires careful attention to detail. According to a research paper, CZTS thin film solar cells are successfully fabricated on flexible Molybdenum (Mo) foil substrates by an electrodeposition-annealing route. The CZTS thin film solar cell was successfully synthesized on flexible Mo foil substrate by the electrodeposition-annealing method with 0.55% power conversion efficiency (CZTS thin film solar cells on flexible .........).

It is important to note that the annealing process should be performed in an Argon atmosphere with some pure sulfur. However, you mentioned that your sample turns black and not usable for the solar cell application when you anneal it at 450 C in Argon atmosphere with some pure sulfur. It is possible that there is an issue with the sulfurization process. Unfortunately, I could not find any information on how to perform the sulfurization process correctly. I will read more when I get time.

I hope this helps! Let me know if you have any other questions.

Source:

(1) CZTS thin film solar cells on flexible Molybdenum foil by ... - Springer. https://link.springer.com/article/10.1007/s10800-020-01494-1.

(2) Annealing And Surface Treatment of Molybdenum Plate [2019/02/27]. https://www.chemetalusa.com/annealing-and-surface-treatment-of-rolled-molybdenum-plate-2019-02-27/.

(3) Investigation of Annealing Conditions on Electrochemically Deposited .... https://www.researchgate.net/publication/305698120_Investigation_of_Annealing_Conditions_on_Electrochemically_Deposited_CZTS_Film_on_Flexible_Molybdenum_Foil.

(4) Impact of molybdenum out diffusion and interface quality on the .... https://www.nature.com/articles/s41598-017-01605-7.

Kaushik Shandilya Thank you