Most SCI journals don't charge publishing fees, but after the papers are published, others will charge for downloading them! At present, there are also many journals that use open access, which can download articles for free, which can improve the citation rate of papers, but it needs to charge a lot of page fees! However, periodicals are still very kind, and you can apply for a reduction or exemption of page fees:

Dear Dr. XXXX or Professor (the surname of the editor or editor-in-chief who issued the decision),

Reply: Ms. XXXX (manuscript number, if any)–XXXX (article title)

I am glad that our paper was accepted and published by XXX (journal name).

We noticed that the publication of manuscripts is charged (or printing color pictures, or any charge). The cost of publishing (or the cost of printing color pictures, or whatever you are charged) seems too expensive for me at present. Although the project was funded by * * * *, the total amount of funding was RMB XXXX (about $XXXX). With this money, we can only try to carry out and complete our experiment, so we don't have enough money to pay for publishing (or printing color pictures, or whatever you are charged).

Therefore, I am writing to you to discuss the possibility that publishing fees (or printing color pictures, or whatever fees you are charged) can be reduced or even exempted. However, if it is difficult for you to give us such a concession, we will make every effort to meet the publishing requirements, including paying the publishing fee (or printing color pictures, or whatever fees you are charged), because it is very important for us to publish this paper in your magazine.

Thank you very much for your consideration and look forward to receiving your reply as soon as possible.

My cordial greetings,

You are sincere,

XXXX (name of correspondent)

XXX (title of correspondent) correspondent