Combustion derived Y doped CuO nanoparticle: its structural, morphological and optical properties

In the present paper, we report Yttrium doped CuO nanoparticles by varying weight ratios as 0.2, 0.4 and 0.6 as wt% of Y synthesized using an energy-efficient and solution combustion method with glycine in use as a fuel. Structural and optical characterization of Y doped CuO was investigated by annealing the samples to 400 °C (as-prepared), 600 °C and 800 °C. X-ray diffraction measurements indicate that the synthesized nano crystallite consists of monoclinic CuO phase with impurity phase (Y₂O₃) of Y at elevated temperature. Scanning Electron Microscopy observations show that the particles are more agglomerated with the addition of Y in CuO. The presence of Y is evidenced by the metal oxide peak shift in FTIR spectra. The effect of annealing and the impurity phase formation of the dopant were observed by the merging of the metal oxide peaks. The optical absorption results show that the optical bandgap energy of Y:CuO nanocrystals were much less as compared to that of the undoped CuO particles. Doping CuO with Y has shifted the absorption edge and narrowing down the E_g due to the existence of excess number of electrons by the trivalent impurity in the conduction band. Increasing the dopant concentration and the annealing has led to the partial curing of copper vacancies which has widened the bandgap. Photoluminescence (PL) spectra at the room temperature showed a strong band edge emission, and thereby confirm an increase in the concentration of defects upon doping with respect to the undoped CuO.