Transport properties of electrodeposited copper telluride (Cu2Te) nanowires embedded in polycarbonate track-etch membrane

Abstract

In this paper, electronic transport properties of electrodeposited copper telluride (Cu2Te) nanowires at room temperature (303 K) embedded in polycarbonate track-etch membranes (Whatman, 6 μm thick, pores density of order 108 pores/cm2) as template with pores of diameter 200, 100 and 50 nm have been reported. Scanning electron microscopy equipped with energy dispersive X-ray spectrometer and X-ray diffractometry (XRD) were used to characterize the morphology and structure of the nanowires. I–V measurements of copper telluride nanowires of different diameter have shown symmetric and ohmic behavior in the voltage range used in this experiment. The temperature (T) dependent electrical conductivity measurements over a temperature (T) range of 308–423 K reveal that the electrical conductivity increases with increasing temperature and decreases as the size of the nanowires reduces. The electrical conductivity (at T ≥ room temperature) was observed significantly higher in copper telluride nanowires of higher diameter compared to lower diameter which attributes to the size effect. The activation energies (E a ) are found to be 2.34, 3.11 and 5.01 meV in low-temperature range of 308–340 K and 0.15, 0.28 and 0.57 meV in high-temperature range of 340–423 K for 200, 100 and 50 nm nanowires respectively. The temperature dependence of electrical resistance measurements has shown the nanowires have negative temperature coefficient of resistance (TCR).