“…Cr, Mn, Ni, Co, Fe) in ZnO can improve its structural, optical, electrical and magnetic properties significantly [9][10][11][12]. Transition metal doped-ZnO nanostructures can be fabricated using different techniques, such as organometallic precursor method [7], microemulsion process [8], microwave hydrothermal process [9], sol-gel synthesis [10], precipitation method [11], physical vapor deposition [12], solvothermal synthesis [13], hydrothermal synthesis [13,14], chemical methods [15] and auto-combustion method [16]. Among all these methods, auto-combustion method yields homogeneous, good quality nanoparticles in a short period of time.…”