Synthesis and characterization of Mg- and Sm-doped ZnO nanoparticles for advanced optoelectronic devices: a comparative study of optical, electrical, and photoluminescence properties
摘要
In this work, nanostructured pristine ZnO, Mg-doped, and Sm-doped ZnO nanoparticles were produced by a sol–gel auto-combustion procedure. The aim was to comparatively study the optical, electrical, and photoluminescence characteristics of these samples for use in advanced optoelectronic devices. The findings show that Sm-doped ZnO has a wide band gap of 3.42 ± 0.001 eV, a narrow absorption range, and a low electrical conductivity of 3.11 ± 0.005 × 10−4 S/cm, which limits its use in optoelectronic devices. Mg-doped ZnO possesses a moderate band gap of 2.92 ± 0.006 eV, a visible absorption range, and high electrical conductivity (8.54 ± 0.000008 × 10−4 S/cm), which supports its use in optoelectronic device applications. Also, XRD and SEM findings show that Mg-doped ZnO has the lowest dislocation density and high crystallinity, reduced grain boundaries, and less agglomeration than pristine ZnO and Sm-doped ZnO. Furthermore, the PL study reveals that Mg-doped ZnO possesses low PL intensity and low charge recombination as compared to Sm-doped ZnO and pristine ZnO. Hence, these results ensure that the alkaline metal ion (Mg) doping is more favorable for doping in ZnO than rare-earth metal ion doping, which makes the potential material for advanced optoelectronic devices.