Investigation on electrical, structural, magnetic, optical properties and EPR studies of CdCu₂O₃ composite oxide prepared via sol–gel method

The present work shows synthesis of 1:2 CdO/CuO (CdCu₂O₃) composite oxide using sol-gel method via nitrate-citrate route. Reitveld refinement of Powder X-ray diffraction (XRD) data reveals presence of two phases: 33.33% of CdO and 66.66% of CuO. Magnetic data recorded using Physical Properties Measurements System (PPMS) shows paramagnetic nature of CdCu₂O₃ at 10, 77, 120 and 320 K. Simulation of the observed electron paramagnetic resonance (EPR) lineshape at 77 K exhibiting four perpendicular lines and poorly resolved four parallel lines using axially symmetric spin Hamiltonian parameters reveals: g_║ = 2.32, A_║ = 102.6 × 10⁻⁴ cm⁻¹, \({\text{g}}_{ \bot }\) ${\text{g}}_{\perp }$  = 2.12, \({\text{A}}_{ \bot }\) ${\text{A}}_{\perp }$  = 21.5 × 10⁻⁴ cm⁻¹ of Cu²⁺ (⁶³Cu I = 3/2, 3d⁹) ions in octahedral [O_1/2-Cu^IIO_4/2-O_1/2]⁴⁻ coordination having Jahn–Teller distortion by elongation in D_4h symmetry. Analysis of DC electrical conductivity result shows a conductivity value of 1.65 × 10⁻⁹ S/cm which implies weakly semiconducting nature of CdCu₂O₃ composite oxide at 300 K.