Sintetização do dissulfeto de molibdênio (MoS2) dopado com paládio (PD) por meio da metalurgia do pó e sua caracterização estrutural, térmica e elétrica

Abstract

This study investigated the synthesis and structural characterization of palladium (Pd)-doped molybdenum disulfide (MoS2) using powder metallurgy. The samples were analyzed by X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and scanning electron microscopy (SEM). The XRD results confirmed the preservation of the hexagonal phase of MoS2. Furthermore, no peaks corresponding to the formation of Pd-containing secondary phases were observed in any of the samples, indicating that the adopted synthesis conditions were appropriate. SEM images revealed morphological changes, with increased surface roughness and particle dispersion, especially in the samples with higher Pd content. Raman spectroscopy showed the presence of the two main MoS₂ peaks at approximately 386.6 cm-1 and 409.2 cm-1, corresponding to the E21g and A1g vibrational modes, respectively. The electrical results of the Pd-doped MoS₂ were consistent with the literature and showed a significant increase in electrical conductivity. However, the formation of agglomerates, grain boundaries, and the absence of adequate thermal treatment limited more substantial improvements. Doping proved essential in controlling the electrical transport properties, highlighting its potential for optimizing the thermoelectric figure of merit (ZT) through defect engineering and controlled doping.