Analysis of defect luminescence in Ga-doped ZnO nanoparticles

Abstract

We applied cathodoluminescence (CL) spectroscopy to evaluate the defect-induced luminescence within ZnO and Ga-doped ZnO (GZO) nanoparticles. The observed emissions from defect sites present in the GZO lattice exhibited a strong dependence on both dopant content and synthesis methods. The strong and broad defect-induced emissions and inhomogeneous population of intrinsic defects in nano-sized ZnO particles could effectively be suppressed by Ga doping, although large dopant amounts caused the generation of negatively-charged defects, VZn and Oi, with a subsequent increase of the luminescence. Upon deconvolution of the retrieved CL spectra into individual sub-bands, the physical origin of all the sub-bands could be clarified, and related to sample composition and synthesis protocol. This study lays the foundation of quantitative CL evaluation of defects to assess the quality of GZO optoelectronic devices.

Defect-related multicolour emissions in ZnO smoke: from violet, over green to yellow

“…Figure 7 reports a synoptic proposal for the interconnected redox processes occurring upon vacuum annealing treatment and that are responsible for the disappearance of some native defects and generation of new ones. The assignement of couple III to Vo + is also supported by investigating the expected reactivity of water on such defect 23,88 , as shown in figure 8. Water splitting fills up the Vo + vacancy, leading to the intensity decrease of couple III.…”

“…In addition, different transitions matching this energy were calculated by several groups. [87][88][89] Finally, this led to the fact that several defects likely to exist in ZnO were suggested as candidates for this PL band. The attribution of the EPR signal at g=2.002 is, on the other hand, hindered by the fact that it lies very close to the value usually reported for free electrons (g  2.00).…”

Luminescence properties of ZnO-M heterostructures fabricated by galvanic-submerged photosynthesis of crystallites

“…Semiconductor nanomaterials have been extensively studied for their applications in optoelectronic devices, catalysis, nanomedicines, and plasmonic devices [1][2][3][4]. Among them, optoelectronic devices are worthy of special attention.…”

Mapping the structural, electrical, and optical properties of hydrothermally grown phosphorus-doped ZnO nanorods for optoelectronic device applications

“…Moreover, the phosphorus in ZnO nanostructures was found to trigger the oxygen vacancy-related photoluminescence (PL) emission in the visible region [8, 16]. Though there have been several reports on the PL emission study of ZnO nanostructures [17–22], a systematic study that can cover the luminescence in the three different and important regimes of the electromagnetic spectra including ultraviolet (UV), visible, and near-infrared (NIR) regimes along with their electrical and structural properties is quite scarce.…”