Structural, Morphological, and Spectroscopic Study of Zn doped Bi1.5Nb1.5CuO7 Pyrochlore Compounds

Abstract

In this study, we synthesized and characterized pyrochlore solid solutions, specifically Bi_1.5Nb_1.5Zn_xCu_1-xO₇(with x values of 0, 0.2, 0.6, 0.8, and 1), for their potential use as catalysts in the degradation of organic pollutants. These pyrochlore compositions were prepared using the solid-solid reaction technique and thoroughly characterized through X-ray diffraction, scanning electron microscopy,Fourier-transformInfrared and UV-vis spectroscopy. XRD analysis confirmed the presence of a cubic pyrochlore structure with Fd3m symmetry. Notably, we observed a consistent linear decrease in the lattice parameter as zinc concentration decreased, demonstrating the successful incorporation of zinc into the pyrochlore lattice. SEM observations revealed dense microstructures with limited intergranular porosity, indicative of structural integrity. Infrared spectroscopic analysis identified vibrations associated with metal-oxygen bonds, further confirming the pyrochlore nature of these compounds. Variations in absorption peak intensities were correlated with the substitution fraction x, primarily attributed to the differing masses of copper and zinc atoms. The energy band gap, determined via the Tauc-plot method, ranged from 2.72 eV (x = 0) to 3.35 eV (x = 1), consistently increasing. These findings underscore pyrochlore materials' potential as catalysts for environmental remediation, particularly in degrading organic pollutants.