Structural, optical and magnetic properties of rare-earth (Nd) element doped CuO nanoparticles

Abstract

The study mainly focused on synthesizing CuO nanoparticles (NPs) and doping these NPs with rare earth element Neodymium (Nd) dopant at various concentrations following chemical co-precipitation method. The purpose of this study was to incorporate Nd dopant into CuO lattice and tune its bandgap, affect its morphology as well as introduce ferromagnetic behavior in the lattice for sensor, solar cell, photovoltaic, magnetic storage devices, high performance motor etc. applications.

In this thesis, chemical co-precipitation method was used to synthesize CuO and rare earth element Neodymium (Nd) doped CuO NPs. To investigate structural, morphological, optical and magnetic properties of CuO and doped CuO NPs, XRD analysis, FESEM, UV-Vis spectroscopy and VSM were used respectively.

From XRD analysis, incorporation of Nd dopant into CuO lattice was verified. FESEM images illustrated that particle shape changed from spherical shaped particles for CuO to agglomerated particles to again homogenously distributed nanospheres by doping CuO with Nd. Indirect band gap values were calculated using Tauc plot and the values reduced from 1.36 eV for CuO to 1.29 eV for 3 mol.% Nd and then increased to 1.31 eV for 5 mol.% Nd doped CuO NPs. It was observed that magnetic hysteresis loop was introduced in Nd doped CuO NPs that demonstrated ferromagnetic properties. Nd dopant resulted in ferromagnetic properties in paramagnetic CuO NPs. Rare earth element Nd doping generates ferromagnetic property in 0.5 mol%, 1 mol%, 3 mol% and 5 mol% Nd doped CuO NPs where, from M-H diagram, extracted values of coercivity (Hc) increased from 258.35 Oe to 741.46 Oe, remanent magnetization (Mr) increased from 7.29 emu/g to 9.956 emu/g and saturation magnetization (Ms) values decreased from 0.1224 emu/g to 0.0948 emu/g.