2026 | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 | 2014 | 2013 | 2012 | 2011 | 2010 | 2009 | 2008
Exploring the effect of partial Ni2+ substitution on the structural, elastic, optical behaviour of Mn1-xNixCr2O4 (x=0.2) spinel chromite material
Authors: Hajji, A.B.; Dhahri, A.; Jeidd, A.; Dhahri, R.; Dhahri, E.; Mariano, J.F.M.L.
Ref.: Ceram. Int. 52(12), 20261-20279 (2026)
Abstract: In the present research paper, a pure phase of Mn0.8Ni0.2Cr2O4 spinel chromite compound was successfully synthesized by means of a sol-gel route. Various techniques have been employed to characterize the material under investigation. Room temperature X-ray diffraction, SEM, FTIR spectroscopy and UV-Visible/NIR spectrophotometer have been employed for the investigation of the structural, morphologic, elastic and optical behaviour. The structural refinement using the Rietveld method gives rise to a pure cubic spinel phase with (Fd-3m) space group. The morphologic exam shed light on how particles agglomerate and grow beyond the nanocrystal system. By computing stiffness parameters through force constants, we derived elastic moduli such as, longitudinal modulus, bulk modulus and rigidity modulus. The material under investigation exhibited lower values for these moduli, as well as the Debye temperature, compared to other spinel chromite compounds. Our sample displayed a brittle mechanical nature on the basis of the Pugh ratio (B/G < 1.75), while the Poisson ratio remained constant at 0.25, thus shedding light on the isotropic elasticity. Optical analysis discussed in terms of absorbance as well as reflectance measurements reveals the semiconducting behaviour of the studied Mn0.8Ni0.2Cr2O4 sample with direct optical band gap of around 1.74 eV. Further analysis of the spectral behaviour of extinction coefficient, refractive index, dielectric constant and non-linear optical response have been taken into consideration. Our study found that the band-gap energy values of the as-synthesized samples were smaller than reported values for MnCr2O4 spinel chromite compound, indicating that Ni2+ substitution offer an opportunity to extend the sunlight absorption range of manganese chromite.
