Electrical conductivity of intermetallic and nanocomposites: A comparative experimental and theoretical study

Abstract

• Four series of intermetallic and metal nanocomposites were synthesized. • The influence of heat treatment, coinage metal, and ferromagnetic material was investigated. • Electrical conductivity increases with heat treatment temperature and sub-zero temperature. • The electrical conductivity of nanocomposites was higher than IMCs and coinage metals. • Experimental finding was supported by the theoretical (computational) study. In an attempt to find room-temperature superconductors, the electrical conductivity of intermetallic and nanocomposites needs to be explored at room and subzero temperatures by different experimental and theoretical methods. For the same, the intermetallic compounds (IMCs) and nanocomposites (NCs) of ZnO, TiO 2 , Al 2 O 3 , and CuO were synthesized by high-temperature reactive synthesis and Sol-gel techniques, respectively. NCs were annealed at 100, 200, 300, and 400 °C. The NCs were characterized by FESEM, XRD, UV visible, and FTIR methods. The theoretical study (DMol3, CASTEP, Forcite, Reflex, and VAMP) were performed to study the electronic and optical properties of metal nanoparticles. The effect of annealing, the coinage metals, and ferromagnetic material, and decrease in temperature on the electrical conductivity of IMCs and NCs were meticulously investigated. The electrical conductivity of NCs increases with heat treatment temperature (400 °C), and with the decrease in temperature (−70 °C). The addition of α-Fe 2 O 3, and coinage metals does not have a significant effect on the increase in electrical conductivity of NCs. The conductivity of NCs was found higher than IMCs and coinage metals. The synthesized NCs can have a large number of applications in nanowires, nano cables, and quantum dots.