Electronic conductivity and strength of GeSbS-AgI chalcogenide glass reinforced by the carbon nanofibers

Due to their excellent chemical properties, mechanical strength and electrical conductivity, carbon nanofibers (CNFs)-doped materials show immense potential in energy storage, electromagnetic shielding, aerospace, and other fields. In this study, we propose a new highly conductive chalcogenide glassy composites: 0.6[40GeS2-60Sb2S3]-0.4(AgI)-xCNFs (GSSA-xCNFs), where x = 0, 0.5, 1.0, 1.5, 2.0 wt%. The mechanical behaviors of the glass composites were significantly improved due to the strong cohesive bonding at the CNFs/glass interfaces. The introduction of 2.0 wt% CNFs has raised the hardness from 1.35 to 1.66 GPa; meanwhile, Young's modulus increased from 22.3 to 25.8 GPa. The doped Ag ions endow the chalcogenide glass with excellent electrical properties. Moreover, the introduction of CNFs further enhanced the DC conductivity of glassy composites from 2.79 x 106 to 4.48 x 10-5 S/m at 293 K due to a percolation network of CNFs formed when its concentration from 0 to 2.0 wt%. Additionally, positive temperature dependence of resistance was observed in the glassy composites, possible mechanisms have been discussed based on the determined thermodynamic features, microscopic morphology, and structural characteristics of the composites. The synergistic effect of Ag+ and CNFs enhances the conductivity of the carbon nanofiber doped chalcogenide glass composites. The strong interface connection can be established between CNFs and glass matrix to improve the mechanical properties. image