A study on the electrical, magnetic and optical limiting behaviour of Pure and Cd-Fe co-doped CuO NPs

Abstract Copper Oxide (CuO) Nanoparticles (NPs) in pure and doped form (cadmium (Cd) - iron (Fe)) co-doped (2 & 4 wt.%)) were developed via employing simple co-precipitation method. PXRD pattern shows that there is no impurity in the single-phase monoclinic structure. The agglomeration of needle-like, flake-like and spherical-like morphologies for undoped and Cd-Fe (2 & 4 wt.%) co-doped CuO NPs are examined through SEM analysis. From UV-Vis DRS spectra, the obtained optical band gap of the synthesized materials was found to be 2.38, 2.62 and 2.77 eV for undoped and Cd-Fe (2 & 4 wt.%) co-doped CuO NPs. PL spectrum confirms the slight variation in emission wavelength compared to undoped CuO NPs. At different temperatures, electrical conductivity measurements of synthesized samples are estimated by the dielectric constant, dielectric loss and ac conductivity with different frequencies. VSM analysis exhibits a maximum saturation magnetization (0.02159 emu/g) for Cd-Fe co-doped CuO NPs (4 wt. %), which reveals the synthesized samples can be a probable candidate for optoelectronics and spintronic device fabrication. The nonlinear absorption and optical limiting properties were investigated by using open aperture Z-scan method under nano pulsed green laser excitation. With increased Cd-Fe concentration, the two-photon absorption coefficient increases from 3.0 × 10 − 10 W / m to 4.8 × 10 − 10 W / m . Both undoped and Cd-Fe co-doped CuO NPs exhibit two-photon absorption induced optical limiting action with lower onset optical limiting threshold and thus can be used for the development of the laser protection devices against widely used high power nano pulsed green laser.