Zn1-xMgxO nanoparticles prepared by the polymeric precursor method: Correlation between photoluminescence and local structure

Femtosecond Pulse Ablation Assisted Mg-ZnO Nanoparticles for UV-Only Emission

“…We also note the identical blue-shift in the NBE for the case of Mg-doped ZnO nanoparticles irrespective of the ablation power used in fs-PLAL. This is clearly attributable to the content of Mg-doping, following earlier work [49]. The emission at 390-410 nm corresponds to transitions to the valence band from Zn + i and Zn 2+ i levels situated 0.22 eV and 0.5 eV, respectively, below the conduction band [37,48].…”

“…While the NBE of Mg-doped ZnO is blue-shifted with respect to pristine ZnO nanoparticles, the green emission in both cases is very similar, showing a broad symmetric feature center at 525 nm. This behaviour is due to the trap-assisted transition from donor level at 2.43 eV (510 nm) above the valence band [ 50 ], which is not influenced by doping [ 49 ]. The unchanged defect emission also indicates that there is no excess of Mg in the ZnO host, which may affect deep levels such as Mg-interstitials ( ), as demonstrated by Trunk et al [ 51 ].…”

CeO2 and CeO2:Pr nanocrystalline powders prepared by the polymeric precursor method: Yellow and red pigments with tunable color

“…The bond cleavage on chemical and thermal environment presents a significant dependence on the order of the bond energies 31,32 . Consequently, the initial cleavage occurs at the Ce‐O bonds with subsequent annealing, which modifies the intermolecular chemical environment and removes a portion of the oxygen from the network along with the carbon 31,32 . Hence, an increase in the number of oxygen vacancies and Ce 3+ ions would be caused by the increase of the annealing temperature as a consequence of the charge compensation, explaining the results of Raman and XPS analysis.…”

“…Doped or pure nanoparticles of CeO 2 have been successfully synthesized through this procedure 29,30 . As this method uses a polymeric resin as a precursor, it has been reported that some materials could contain carbon atoms even after the pyrolysis procedure, creating defects in the lattice, such as interstitial or substitutional carbons 31,32 . The increasing of the annealing temperature causes the initial cleavage of cation‐O bonds, resulting in the removal of the O atoms along with C atoms 31,32 .…”

“…As this method uses a polymeric resin as a precursor, it has been reported that some materials could contain carbon atoms even after the pyrolysis procedure, creating defects in the lattice, such as interstitial or substitutional carbons 31,32 . The increasing of the annealing temperature causes the initial cleavage of cation‐O bonds, resulting in the removal of the O atoms along with C atoms 31,32 . Concerning nanostructured CeO 2 samples, the loss of oxygen at the surfaces of the nanoparticles causes typically the formation of nonstoichiometric compounds of the type CeO 2‐δ 6 .…”