Structural and vibrational investigations on Ge34Sb66 solid solutions produced by mechanical alloying

Highlights: •A Ge34Sb66 solid solution was prepared by mechanical alloying. •X-ray diffraction results indicate complete dissolution of Ge on the Sb matrix. •Raman measurements indicate the presence of nanocrystalline Ge dispersed in the matrix. -- Abstract: A nanostructured solid solution Ge34Sb66 was produced from Ge and Sb by mechanical alloying and its structural and vibrational properties were investigated by X-ray diffraction (XRD) and micro-Raman spectroscopy. The Rietveld refinement of the XRD measurements allowed the investigation of the evolution of the solid solution with the milling time. The Bragg peaks of the Sb solvent phase showed a strongly reflection-indices-dependent line broadening due to the spatial variation of the Sb/Ge ratio. The asymmetric broadening in the deformed peaks was analyzed considering the Stephens model. Volume fractions of crystalline and interfacial components of the milled powder were estimated from the XRD patterns. Although XRD measurements indicated the formation of a solid solution, Raman measurements revealed the presence of nanocrystalline Ge, and its crystallite size was estimated from the Raman analysis