The correlation of several defects and optical and magnetic properties with Fe content in Zn_1−xFe_xAl₂O₄ (0.01 ≤ x ≤ 0.40) nanocrystals has been scrutinized through X‐ray diffraction, O K‐edge X‐ray absorption near‐edge structure, FT–IR, diffuse reflectance, photoluminescence and electron spin‐resonance spectroscopies, and vibrating sample magnetometry. Increasing Fe content causes elongation in the octahedral units of the lattice, accompanied by distortion in the octahedral coordination. Fe introduces non‐radiative centres in the forbidden gap, thereby tuning the band gap from 4.37 to 3.88 eV and eliminating emission in the visible region. Zn vacancies are found to tail off, while , and Fe_Al^× antisite defects increase in concentration with increasing Fe content. Inhomogeneous broadening of spin‐resonance signals infers strong spin‐lattice interactions of Fe³⁺ ions at distorted octahedral and non‐symmetric tetrahedral sites. A transition is observed from paramagnetism to superparamagnetism at higher Fe concentrations. A visual colour change from pearly white to orange–brown is observed in Zn_1−xFe_xAl₂O₄ nanocrystals with increasing Fe content, revealing its potential candidature for pigments in the paint and dye industries.

中文翻译：

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Zn1-xFexAl2O4（0.01≤x≤0.40）纳米晶体中缺陷产生和光学性能调整的机械原理

几个缺陷和光学性能和磁性能的与锌Fe含量的相关性_{的1- X}的Fe _X的Al ₂ ö ₄（0.01≤ X ≤0.40）纳米晶体已经通过X射线衍射审查，O- ķ边缘X射线吸收近边缘结构，FT-IR，漫反射，光致发光和电子自旋共振光谱学以及振动样品的磁力分析。Fe含量的增加导致晶格的八面体单元伸长，并伴随八面体配位畸变。铁在禁带中引入了非辐射中心，从而将带隙从4.37 eV调整到3.88 eV，并消除了可见光区域的发射。锌空位被发现尾关断，同时，和Fe_的Al ^×反位缺陷随Fe含量增加浓度。自旋共振信号的不均匀展宽推断出Fe ^3+的强自旋-晶格相互作用在扭曲的八面体和非对称四面体位点离子。在较高的铁浓度下观察到从顺磁性向超顺磁性的转变。随着Fe含量的增加，在Zn _{1- x} Fe _x Al ₂ O ₄纳米晶体中观察到从珍珠白到橙棕色的视觉颜色变化，揭示了其在油漆和染料工业中对颜料的潜在候选资格。