Hello Siti Raihan Hamzah,

The peaks position in a XRD pattern are related to the unit cell parameters. According to Braggs Law:

n.lambda = 2d.sen(theta)

You can calculate the peaks position of your compound. Basically, if your peaks are all shifted to left or right, compared to commercial samples, it means that your compound has a unit cell a little bit different from the commercial sample. And according to Bragg's Law, being "shifted to the right" means a smaller unit cell, and it doesn't mean you did wrong, we don't have to get exact results compared to commercial samples.

Fell free to reply if you need any extra help.

Sincerely,

Ricardo Tadeu

Dear Siti Raihan Hamzah ,

You should share some more details about your sample(s); are they a

'simple' mixture of the mentioned components/phases?

I assume that TiO2, PVC and ENR50 are separate phases; which do not affect the lattice constants of P25-TiO.

Your peak shifts might be due to an experimental issue...

You should

a) play around with the sample height adjustment and see what is happening with your peak positions (peaks shift(s) vs sample height adjustment)

and

b) please check the 'zero' of your angular scale(s); there is a quite constant shift in 2theta over the whole pattern...

What does the operator of the XRD system said about that issue? He should have enough experience and expertise...

Best regards

G.M.

In my opinion, the problem will be the displacement of the sample from the correct position. It will be necessary to verify the alignment on the standard and possibly measure the samples again. Even small variations in sample height are a problem.

Peak shift and tilting of peaks are possible if Twinning and stacking faults are present. But shifting of all peaks to higher angle is rather unusual. You may try for zero shift error correction, which is often encountered in powder XRD..