Surface dangling bonds foisted atypical deep ultraviolet emission in Zn1−xFexO nanoparticles synthesized by thermal decomposition method under nitrogen atmosphere

Highlights: • Zn_1−xFe_xO (x = 0, 0.01, 0.03 and 0.05) nanoparticles synthesized by thermal decomposition method under nitrogen atmosphere. • Unusual deep ultra violet emission is noticed in Zn_1−xFe_xO nanoparticles. • Formation of O 2p states in the valence band due zinc vacancy related dangling bonds at the surface is revealed. • Dominant blue emission is noticed in Zn_1−xFe_xO nanoparticles. • Coexistence of ferromagnetic and paramagnetic behaviors in all samples is noticed. -- Abstract: An uncommon deep ultraviolet emission (DUV) is reported for the first time in Zn_1−xFe_xO (x = 0, 0.01, 0.03 and 0.05) nanoparticles synthesized by thermal decomposition method under inert nitrogen atmosphere. The zinc vacancies induced oxygen terminated polar surface created dangling bonds localized on O, which in turn has the holes in O 2p valance band. Further, the electronic transitions to these O 2p states result in unusual DUV emission in all samples. The 1931 CIE diagram reflects the dominant blue emission from all the samples in the visible region. The exhibition of paramagnetic and ferromagnetic behaviors in pure ZnO reveals the contribution from defects states towards the magnetic properties. An increment in the paramagnetic component with suppression of ferromganetic nature upon increasing the Fe doping concentration is attributed to the antiferromagnetic coupling effect between the nearest Fe ions. The calculated coercivity and retentivity values emphasize the samples are weakly room temperature ferromagnetic in nature.