Pretty sure there should be a way with XRD as well, but if you have access to XPS I recall that rutile and anatase have different Cr peak positions that can be seen.

thanks a lot for guidance and response

Brookite present in the sample mean it's an amorphous. I also found brookite in the samples. XRD is the best method identified anatase, rutile and brookite phases. Lower calcined temperature will give you brookite phases. I found at 300 C. Higher temperature will results brookite phase disappear from the sample.

Of course XRD is the best way.

I recommend XRD you can also calculate crystaline size and lattice constants, yield strength

Dear Samane Mohammadpour ,

As it was recommended above by our colleagues, XRD will be efficient to identify the TiO2 three phases. Moreover, using the simple Scherrer formula will give you an idea on the crystallite size of each of the three phases.

Now, if you want to quantify your three phases ratio in the sample and get a precise crystallite size calculation, I would recommend you to use the Rietveld refinement if possible which is the best way to get these informations.

Dear Kasun Laknath ,

Your results depend of many conditions such as (for instance) the particle size of the studied sample. For nanoparticles, the thermodynamic phases stability can be strongly different than that of bulk material as it is suggested in this reference :

https://doi.org/10.1016/j.materresbull.2007.11.003

Thus, I dont think it is so simple to assert, relying solely on temperature, that one of the three phases will be preferential.

Regards