Structural, thermal and optical characteristics of Fe _1−X Zr _X alloy by using mechanical milling approach: influence of Zr⁴⁺ ion

Abstract

By changing Zr concentrations, Fe1-x-Zrx (x= 0.25 & 1 at.%) alloys were successfully produced in an argon atmosphere using the mechanical alloying method. The produced Fe1-x-Zrx alloys were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersion X-ray analysis (EDAX), fourier transform infrared spectroscopy (FTIR), thermogravimetry analyzer (TG-DTA), ultraviolet-visible spectroscopy (UV–vis) absorption, and photoluminescence (PL) spectroscopy. According to XRD pattern analysis, the preparation alloys had a cubic crystalline structure and a complete solid solution formation. The average crystallite size for the 0.25at.% Zr concentration is found to be 7.79 nm and 11.8 nm for the 1 at.% Zr concentration. The TEM-dark field image confirms that the grain size is in the nanometric range (<100 nm). TEM-SAED spotty continuous ring pattern confirmed the complete solution formation is well correlated with the XRD results. The elemental distribution of the mechanically alloyed samples shows that Zr elements are homogeneously distributed in the Fe matrix. Bands at 3428 cm-1 in the FTIR spectrum have been linked to O–H stretching vibrations. CH2 and CH stretching vibrations were associated with peaks of about 2920 cm-1 and 2850 cm-1. The weight loss and gain changes were observed and represented in the TG-DST graph; we found that overall weight changes are + 10.7% (gain) at 1023oC for Fe 1-x-Zr x (x=0.25 at.%) alloy. The UV-visible absorbance edge revealed a blue shift when Zr was added, indicating alloy production. The energy band gap of materials was calculated using UV-vis, and it has been observed that the band gap reduces as Zr concentration increases. Zr was added to Fe1-x-Zrx alloy nanoparticles, resulting in 514 nm and 775 nm emission wavelengths. The higher PL emission peak was 514 nm at 0.25 at.% of Zr.