Multifunctional Nd³⁺-doped α-γ bismuth oxide (Bi₂O₃) homojunction nanoparticles were successfully synthesized through metamorphosis from the α-β Bi₂O₃ homojunction via a low temperature solvothermal method. The structural and optical properties were thoroughly characterized by different methods. NIR reflectance spectroscopy revealed that 2 wt% Nd³⁺-doped Bi₂O₃ exhibited about 90% NIR reflectance. The CIE-L*a*b* 1976 colour analysis showed a b* value of 50.72, surpassing that of the commercially available yellow pigment Zircon Yellow, which has a b* value of 43.3. The transformation from α-β to α-γ Bi₂O₃ was controlled by dopant concentration, with the band gap decreasing as the Nd³⁺ content increases. The synthesized materials demonstrated efficient photocatalytic activity, degrading model pollutant methylene blue and the antibiotic ceftriaxone sodium under sunlight. This was investigated using UV-visible spectroscopy and LC-MS. The α-γ Bi₂O₃ homojunction presents a promising new direction for eco-friendly cool yellow pigments that degrade organic pollutants under sunlight showing upconversion luminescence and antibacterial activity.

中文翻译：

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Nd3+ 掺杂 α-γ 氧化铋均结纳米粒子的合成：一种智能多功能太阳能光催化剂


通过低温溶剂热法，从 α-β Bi₂O₃ 同结，成功合成了多功能 Nd³⁺ 掺杂的 α-γ 氧化铋 （Bi₂O₃） 同结纳米颗粒。通过不同的方法对结构和光学特性进行了彻底表征。近红外反射光谱显示，2 wt% Nd³⁺ 掺杂的 Bi₂O₃ 表现出约 90% 的 NIR 反射率。CIE-L*a*b* 1976 颜色分析显示 b* 值为 50.72，超过了市售黄色颜料锆英黄的 b* 值为 43.3。从 α-β 到 α-γ Bi₂O₃ 的转变受掺杂剂浓度的控制，带隙随着 Nd³⁺ 含量的增加而减小。合成的材料表现出高效的光催化活性，在阳光下降解模型污染物亚甲蓝和抗生素头孢曲松钠。使用 UV-可见光谱和 LC-MS 对此进行了研究。α-γ Bi₂O₃ 同结为环保型冷黄色颜料提供了一个有前途的新方向，这种颜料在阳光下降解有机污染物，表现出上转换发光和抗菌活性。