X-Ray Fluorescence (XRF) is widely used technique for detection of elements in a given material and to study its composition. In the photoelectric process, an incident radiation of energy (E) more than the threshold limit (WO) of bound electron in any atomic shell strikes the electron and gets entirely consumed and the electron with kinetic energy equal to (E-WO) is fired out, resulting in photoelectric emission (Grieken and Markowicz, 2OO2). Photoelectric effect arises with tightly constrained electrons and the possibility is maximum at the photon energy slightly greater than the absorption edge of electron. Therefore, the photoelectric emission not only depends on the energy of incoming radiation but also on the atomic number and quantum level of the electron in an atom. The process of photoelectric effect leads to vacancy creation and hence a chance for electron to jump from higher energy state to lower state. This gives rise to emission of characteristic X-rays whose frequency (f ) give information about the atom (atomic number Z) according to Mosley's law (1913).