Influence of Ge4+ doping on photo- and electroluminescence properties of ZnGa2O4

Energetic, Electronic, and Optical Behavior of Intrinsic Charge Carrier-Trapping Defects in Ge-Doped ZnGa2O4: Insights from a DFT Study

“…There occurs a distortion in the GaO 6 unit, which is also indicated in the experimental observation. 37 It can be noted that some of the Ga−O and Zn−O bond lengths are found to be relatively lower in the presence of V Zn and V Ga . For antisite defects, a small change in the cell parameter is observed.…”

“…This has also been indicated in the experimental study. 37 It can be observed that the effective gap is reduced significantly in the presence of intrinsic defects, like V O , V Zn , V Ga , and (Ga Zn , Zn Ga ). For V O , the band gap reduction is due to discrete midgap states, whereas for the other systems, no localized midgap states are observed.…”

“…This is attributed to the experimental observation of the enhancement of optical property due to the dominance of other vacancies over oxygen vacancy. 37 In these cases, there occur an elevation of the VBM and a downward shifting of CBM, resulting in the reduction in the band gap to 3.09 and 2.73 eV, respectively. This is very much consistent with the experimental observation of the role of V Ga toward improved optical behavior of Ge-doped ZnGa 2 O 4 .…”

“…Rare-earth ions, which are very popular activators, have been doped into ZnGa 2 O 4 , and high fluorescence efficiencies and very narrow line fluorescence bands have been observed . There have been several efforts to enhance the optical properties of ZnGa 2 O 4 by doping with elements other than transition metals and rare earth elements, like Si, Ge, and In . In particular, Ge has been employed in combination with other dopant elements in many studies to tune the optical properties. ,, It has been found that the local environment of the dopant element suffers severe distortion in the presence of various intrinsic defects, including lattice vacancy defects and antisite defects. ,, The electronic structure plays a decisive role in the optical applications, including photocatalysis, photo-electrocatalysis, and photoluminescence.…”

Improvement of Luminescence Characteristics of ZnGa2O4:Tb3+ Nanophosphors by Ce3+ Codoping

“…[17][18][19] Furthermore, ZnGa 2 O 4 is a spinel structure with Zn 2 + in a tetrahedral position and Ga 3 + in an octahedral position. [20,21] ZnGa 2 O 4 material is therefore suitable substrate for rare earth ion doped long afterglow phosphor, [22][23][24] such as ZnGa 2 O 4 :Yb 3 + ,Er 3 + ,Cr 3 + , [25] ZnGa 2 O 4 :Mn 2 + , [26] ZnGa 2 O 4 :Tb 3 + , [27] and ZnGa 2 O 4 :Li + , [28] etc. At the same time, considering the high sensitivity of human eyes to green light, [29] the development of green long afterglow material plays an extremely important role in practical application.…”