Caracterização da jacutingaíta (Pt2hgSe3) com a indução de defeito por espectroscopia raman

Abstract

Jacutingaite (Pt2HgSe3) is a mineral recently discovered in Minas Gerais, in the Itabira district, and it exhibits a robust topological phase with a lamellar crystalline phase that has been re- cently characterized. Owing to its unique properties, research on jacutingaite has increasingly focused on identifying and understanding these features. In this context, the aim of this work is to characterize jacutingaite using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), atomic force microscopy (AFM), and Raman spectroscopy. Also, the aim was to investigate its properties, potential, and real-world applications, including the effects of induced defects. Initially, the methodology involves optical and spectroscopic characterization of the material through white-light microscopy and Raman spectroscopy performed with a 785 nm laser and a 50× magnification objective. Defects were induced in the jacutingaite structure via Raman spectroscopy. Subsequently, atomic force microscopy, was employed to analyze the effects caused by the laser. The results show that SEM characterization of jacutingaite revealed its lamellar morphology, displaying patterns consistent with its crystalline phase. EDS analysis confirmed the expected chemical composition and identified traces of other elements, possibly associated with oxidation processes of the sample. Raman analysis revealed the emergence of a peak at 60 cm−1 , theoretically predicted but absent in measurements without defects. Moreo- ver, it was found that the thickness of jacutingaite grains and the sample’s degradation directly influence the Raman spectra. Thicker samples exhibited more intense and well-defined peaks, while thinner samples showed lower intensity and absence of certain vibrational modes. AFM analysis of jacutingaite was limited by image acquisition failures, low resolution in one of the samples, and surface damage caused by Raman laser degradation. The results obtained in this work confirm that defects impact the vibrational response of the material, contributing to a deeper understanding that is crucial for future industrial applications.