Depends on you diffractometer setting. In a classical Bragg-Brentano diffractometer you get the convolution of the wave-length distribution with the receiving slit width (on the 2theta scale).

As from your reference figure, not much of difference is markable in the peaks.

However, there might be two reasons that can be looked upon for the peak broadening of the sample:

i) instrumental broadening: Diffraction profiles are broadened depending on the instrumental and optical conditions used, the instrumental broadening being related to the breadth of the X-ray source, flat specimen surface and axial divergence of the X-ray beam. You can use this reference: https://www.sciencedirect.com/science/article/abs/pii/B9780080441634500103;

ii) Stress or thermal expansion of the single crystal in the due to the induced mesopores in the system. Please have a look on this article, which might be helpful: https://www.nature.com/articles/s41467-018-04113-y.

Thanks

Vivek Shukla, May be by the following reasons--

i) For the larger shift towards 2Theta is due to sample displacement.

ii) For the throughout constant 2Theta is a misalignment in the system.

iii) For the other cases, it is related to the sample 2Theta.

iv) For the shift towards right is due to expansion of the lattice. May by stress, substitution elements or non-stoichiometric phase.

v) The shift to right (higher 2Theta) shows lattice contraction, while a shift to left (low 2Theta) is due to the expansion in the lattice.