Atomic order-disorder engineering in the La2Zr2O7 pyrochlore under low energy ion irradiation. Issue 14 (15th July 2021)

• Record Type: Journal Article
• Authors: Panghal, Asha; Kumar, Yogendra; Kulriya, P.K.; Shirage, Parasharam M.; Singh, N.L.
• Is Part Of: Ceramics international. Volume 47:Issue 14(2021)
• Page Start: 20248
• Page End: 20259
• Publication Date: 2021-07-15
• Subjects: La2Zr2O7 -- Structural deformation -- ion irradiation -- Cation/anion disordering -- Lattice swelling; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2021.04.032
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Cation and anion disordering affect the structural and electronic properties of the isometric A2 B2 O7 pyrochlore materials. Here, we report a study on the structural response of La2 Zr2 O7 at two different temperatures (300 K and ~88 K) as a function of ion fluence (1 × 10 13, 5 × 10 13, and 1 × 10 14 ions/cm 2 ). The effect of ion fluence and irradiation temperature on the structural properties have been investigated using the grazing angle x-ray diffraction, Raman spectroscopy, and high-resolution transmission electron microscopy. GIXRD results confirmed that the weakening/broadening of the diffraction peaks and lattice volume expansion increases monotonically as a function of ion fluence at both the temperatures and are more pronounced at ~88 K. The cation and anion disordering appear to be ion fluence and irradiation temperature-dependent. Raman spectroscopy shows that the atomic disordering is more pronounced with enhanced ion fluence and revealed the involvement of the X 48f parameter in the enhancement of disordering in the system. The HRTEM analysis revealed that the deterioration in the atomic ordering (amorphization) is significantly more pronounced at ~88 K. The qualitative analysis of cation/anion disordering and structural deformation revealed that irradiation parameters play a crucial role in developing and altering the properties of the pyrochlore materials for the technological applications. Graphical abstract: Variation of superlattice reflections, cell volume, cation disorder, and "x" parameter of 48f oxygen with ion fluence (1.0 × 10 13, 5.0 × 10 13, and 1.0 × 10 14 ions/cm 2 ) upon ion irradiation at both temperatures. Image 1 Highlights: La2 Zr2 O7 pyrochlore samples were successfully irradiated at ~88 K and 300 K using 500 keV Kr 2+ ions. GIXRD confirmed the lattice volume expansion and cation/anion disordering with enhanced ion fluence. The lattice volume expansion and degree of disorder appear to be ion fluence and irradiation temperature dependent. Raman spectroscopy revealed the involvement of the 48f oxygen in enhancing the disorder in the system. The HRTEM analysis indicates the significantly higher deterioration of the atomic ordering at ~88 K than 300 K.