Is this older discussion helpful?

https://www.researchgate.net/post/What_is_the_different_of_C-F_C-F2_and_C-F3_bond_in_C1s_or_F1s_of_XPS_result2

Semi-ionic C-F bonds are essentially covalent, with which, however, the conjugated C-C bonds are preserved between carbon atoms unbounding to fluorine with the F-C-C angle of 90 • and the neighboring C-C bond length of ∼0.14 nm (Sato et al., 2004; Figure S2B).

You can see the following link:

Article On the so-called “semi-ionic” C–F bond character in fluorine–GIC

I did not find a peak for (~288 eV) C-F in C1s. But, F1s showed peaks at 685.10 eV (ionic C-F) and 686.40 eV (semi ionic C-F). How could I explain it? Is this confirm the making of C-F or something else.

Are C and F the only elements in your dots or are other signals present as well?

Just to exclude that the appearance of ionic F- isn't associated to something else.

Sulfur, nitrogen, fluorine, and oxygen are also present.

Presence of HF be the reason behind ionic Fluoride?.

Is it possible that you have ammonium fluoride or an organic derivative thereof present? Hydrogen cannot be distinguished by XPS elemental analysis and if nitrogen is present, that would be a potential source for ionic fluoride.

Thank you, sir. Yes, ammonium fluoride is the precursor for CDs synthesis. Ionic fluoride is cleared.

But, can semi ionic fluoride bond may form?