FTIR may reveal a lot about the chemical and structural characteristics of your material. A short literature search will be convincing enough I would say. But be aware of the spatial resolution limitations of FTIR: The wavelength of IR spectroscopy is between 1.5 and 10 microns, limiting the resolution to ~ 5 microns in IR microscopy. This can be improved by applying an ATR set-up.
From your question I understand you are working on nano-particles. I can imagine that a higher spatial resolution is desirable. As an alternative you may consider Raman microscopy. It will give similar information compared to IR but with a higher spatial resolution (~0.5 micron).