Multifaceted investigations of co-precipitated Ni-doped ZnO nanoparticles: Systematic study on structural integrity, optical interplay and photocatalytic performances

Abstract

The present study demonstrates the successful synthesis of ZnO and nickel doped ZnO NPs by co-precipitation method. XRD analysis, confirms hexagonal wurtzite structure. The crystallite size increased from 31 to 45 nm with increasing Ni ions and a reduction in the unit cell volume, owing to the smaller ionic radius of Ni2+ compared to Zn2+. PL spectra were observed for pristine ZnO, associated with near band edge emission band, arising from the recombination of free excitons. Due to the splitting of orbitals caused by the presence of magnetic ions, the optical bandgap is found to be decreasing whereas an increase in the occupancy of 3d electrons. The absorption band observed corresponds to the stretching mode below 450 cm−1. A distinctive peak at around 436 cm−1 was identified in the Raman spectra, indicating the high-frequency branch E2 mode in ZnO. Ni-doped (Zn0·91Ni0·09O) NPs achieve about 80 % photodegradation of MEG dye.