Tuning of energy gap, structural, FTIR and photoluminescence examination of Ni, Sn dual doped ZnO nanoparticles

Abstract

Ni, Sn dual doped ZnO nanostructures were prepared with Sn = 0% to 5% using sol-gel route. Phase transparency of the synthesized samples was validated by x-ray diffraction (XRD) studies. Secondary phase was noticed at Sn = 5% which contains impurity SnO2 with orthorhombic structure at 2θ ∼ 38.1°. The diminishing crystallite size by Sn substitution authenticated the inclusion of Sn in the Zn–Ni–O lattice. The anisotropic changes observed in lattice parameters and volume ascribed to the lattice disorder produced with Sn-doping and the ionic mismatch among Zn2+ (0.074 nm) and Sn4+ (0.069 nm). The elevation in absorption and the reduction in band gap by Sn-doping signified that they are helpful for photocatalytic and opto-electronic applications. The enhanced green PL emission by Sn doping is discussed based on the defect states like oxygen vacancies.