Low voltage varistor values and structural analysis for CuO and Ag nano–composite particles

Abstract

Sol – Gel auto combustion method was used to synthesis Copper oxide nano powders whereas, Top—Down method was used to obtain Ag nano – powders, respectively. Various structural studies (XRD, FTIR), thermal studies (TGA), molecular studies (Raman) and morphological studies (FESEM, EDX, PSA) were studied using 4 varying nano structured compositions: CA1 [CuO, 1:0], CA2 [CuO + Ag, 1:1], CA3 [CuO + Ag, 1:2] and CA4 [Ag, 0:1]. TGA characterisation revealed 600 °C as calcination temperature for CuO which was in accordance with the theoretical data. XRD and FTIR analyses confirmed the formation of the desired nano-crystalline structures through the identification of characteristic structural peaks. Raman spectroscopy displayed \({\text{C}}_{2\text{h}}^{6}\text{ C}2/\text{c}\) and \({\text{O}}_{\text{h}}^{5}\text{Fm}3\text{m}\) as space groups for CuO and Ag nano – structures, respectively. An increase in the values for non – linear coefficient (α) was obtained for the composite mixtures, which meant an increase in the Ohm’s Law region was observed. The current (I_N) and voltage (V_N) values for varistor studies exhibited smaller value changes which made low – voltage valued sectors as their possible applicational field.