IM2NP, CNRS UMR 7334, FST, Aix-Marseille Université, F-13397 Marseille Cedex 20, France.
Nanotechnology. 2017 Jul 14;28(28):285705. doi: 10.1088/1361-6528/aa716a. Epub 2017 May 5.
Zinc oxide (ZnO) nanorods grown by the low-temperature (90 °C) aqueous chemical method with different cobalt concentration within the synthesis solution (from 0% to 15%), are studied by electron paramagnetic resonance (EPR), just above the liquid helium temperature. The anisotropic spectra of substitutional Co reveal a high crystalline quality and orientation of the NRs, as well as the probable presence of a secondary disordered phase of ZnO:Co. The analysis of the EPR spectra indicates that the disappearance of the paramagnetic native core-defect (CD) at [Formula: see text] is correlated with the apparition of the Co ions lines, suggesting a gradual neutralization of the former by the latter. We show that only a little amount of cobalt in the synthesis solution (about 0.2%) is necessary to suppress almost all these paramagnetic CDs. This gives insight in the experimentally observed improvement of the crystal quality of diluted ZnO:Co nanorods, as well as into the control of paramagnetic defects in ZnO nanostructures.
采用低温（90°C）水热化学法在合成溶液中添加不同钴浓度（0%至 15%）生长氧化锌（ZnO）纳米棒，在接近液氦温度下通过电子顺磁共振（EPR）进行研究。取代钴的各向异性谱表明 NRs 具有高结晶质量和取向，以及 ZnO:Co 的可能存在的次要无序相。EPR 谱的分析表明，在 [Formula: see text] 处消失的顺磁本征核缺陷（CD）与 Co 离子谱线的出现相关联，这表明前者逐渐被后者中和。我们表明，合成溶液中只需少量的钴（约 0.2%）就足以几乎完全抑制所有这些顺磁 CD。这为实验观察到的稀释 ZnO:Co 纳米棒的晶体质量的提高以及 ZnO 纳米结构中顺磁缺陷的控制提供了深入的了解。
