Time-resolved spectroscopic study of energy transfer in ZnO:EuCl3 phosphors

Effect of Eu Doping on the Physical, Photoluminescence, and Photocatalytic Characteristics of ZnO Thin Films Grown by Sol–Gel Method

“…interstitial sites rather than the sites of Zn 2+ ions, as the 5D 0 → 7F 0 transition is strictly forbidden due to the same total angular momentum . In addition, it has been observed that the intensity corresponding to 5 D 0 → 7 F 2 transition at 612 nm increases as the doping concentration increases and could be attributed to the transfer of energy from ZnO host to Eu 3+ ion …”

Dependence of energy transfer and photoluminescence on tailored defects in Eu-doped ZnO nanosheets-based microflowers

“…Because the luminescence lifetime of RE ions is in the micro and milli-second time scale, 10 2 times slower than decay of excitons in ZnO, and this mismatch makes direct energy transfer from ZnO to RE ions very impossible [15]. Furthermore, the quenching effect on RE emission appears due to the self-activated transitions in the ZnO matrix [16]. Fortunately, energy transfer can be facilitated by the presence of intrinsic or extrinsic defects as energy trapping centers in various systems, such as SiC:(N, Er), ZnO:(N, Eu) and ZnO:(F, Eu) [17,18], which suggest that the introduction of the appropriate trap centers is crucial for efficient ZnO → Eu 3+ energy transfer.…”

“…Fortunately, energy transfer can be facilitated by the presence of intrinsic or extrinsic defects as energy trapping centers in various systems, such as SiC:(N, Er), ZnO:(N, Eu) and ZnO:(F, Eu) [17,18], which suggest that the introduction of the appropriate trap centers is crucial for efficient ZnO → Eu 3+ energy transfer. Park et al reported that chlorine impurities can assist red emission in Eu 3+ -doped ZnO [13,16]. In a recent work, Zeng et al claimed that Eu 2+ ions act as trapping centers in Eu-doped ZnO microflowers and transfer energy to the Eu 3+ ions [19], consequently leading to red emission.…”

Effective Doping of Er3+ in ZnO Nanoparticles to Control Its Luminescent Properties

“…The synthesized ZnO nanostructures have some by‐products, intermediate impurity on the surface of the lattice which behaves as defect centers for the emission of green luminescence. The defect group are closely bound on the surface of ZnO by dangling bond . Pure ZnO nanoparticles reveal a broad visible emission at about 518 nm excited at a wavelength of 325 nm and a sharp UV near band edge emission (NBE) at about 382 nm.…”