The effect of Fe³⁺ ionic substitution in hydroxyapatite (Ca_10‐xFe_x(PO₄)₆(OH)₂) was studied using structural modifications, resulting in an improvement in UV absorption through a tailored optical band structure. Ca²⁺ of HA being larger compared to Fe³⁺ contributes to the shrinkage of the lattice. Undoped HA has a peak at 1085 cm⁻¹ (ʋ₃ PO₄³⁻) which is shifted to 1033 cm⁻¹ for Fe‐HA, because of the perturbation in HA structure. An improvement of UV absorption in the entire UVA and UVB range with an increase in Fe content because of a decrease in bandgap from 5.9 eV to 2.1 eV with undoped and doped HA. Theoretically obtained band gap and optical behaviour of the systems are well correlated with the experimental findings. Moreover, the use of marine biowaste from cuttlefish bone, as the source of HA; low cost and promising UV absorption can have a potential application as UV protective sunscreen filters.

中文翻译：

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Fe3 +取代对羟基磷灰石结构改性和能带结构调节的UV吸收的影响

使用结构修饰研究了Fe ³⁺离子取代在羟基磷灰石（Ca _10-x Fe _x（PO ₄）₆（OH）₂）中的作用，从而通过定制的光学带结构改善了UV吸收。HA的Ca ²⁺比Fe ^3+大有助于晶格的收缩。未掺杂的HA在1085厘米具有峰值^-1（ʋ ₃ PO ₄ ^3-），其被转移到1033厘米^-1对于Fe‐HA，是因为HA结构受到干扰。由于未掺杂和掺杂的HA的带隙从5.9 eV降低到2.1 eV，Fe含量的增加使整个UVA和UVB范围内的UV吸收得到改善。从理论上获得的带隙和系统的光学行为与实验结果紧密相关。此外，利用墨鱼骨中的海洋生物废物作为HA的来源；低成本和有希望的紫外线吸收技术可以作为紫外线防护防晒滤光片潜在应用。