In the present study, the utility of Pr^3+/Pr⁴⁺ and Bi³⁺/Bi(0) redox couples for oxidation and reduction reactions is demonstrated by synthesizing bismuth-substituted PrO_1.833 samples following a solution combustion method. The samples retained the defect fluorite structure of PrO_1.833 with the inclusion of up to 40 mol% of bismuth, beyond which the rhombohedral structure emerged. The microscopic analysis also reinforced the defect fluorite structure of these samples. The lattice expanded with the inclusion of bismuth. The samples had porous morphology, and the X-ray energy dispersive spectral analysis ensured the presence of Pr and Bi closer to the nominal molar ratio. The intense band at 565 cm⁻¹ in the Raman spectrum shifted to higher values with a progressive increase in bismuth content due to the creation of more oxygen vacancies. In Pr_0.60Bi_0.40O_2−δ, Pr existed in +3 and +4 oxidation states, as revealed by the X-ray photoelectron spectral analysis. The photoluminescence spectra consisted of 4f–4f transitions of Pr³⁺ and emission in the blue region (due to oxygen vacancies). Both Pr_0.60Bi_0.40O_2−δ and PrO_1.833 remained paramagnetic in field-dependent and temperature-dependent measurements down to 2 K. The effective magnetic moment, retentivity, and coercivity decreased on moving from PrO_1.833 to Pr_0.60Bi_0.40O_2−δ. The bismuth-substituted samples catalyzed the oxidative degradation of xylenol orange and methyl orange. The degraded products from these reactions were identified. The bismuth-substituted samples also catalyzed the reduction of nitroaromatics. These transformations followed pseudo-first-order kinetics.

中文翻译：

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通过在有缺陷的萤石结构的PrO1.833中引入Bi3 +可以产生双功能催化性能。

在本研究中，通过溶液燃烧法合成铋取代的PrO _1.833样品，证明了Pr ^{3 + /} Pr ⁴⁺和Bi ³⁺ / Bi（0）氧化还原对用于氧化和还原反应的_效用。样品保留了PrO _1.833的萤石缺陷结构，并包含了高达40 mol％的铋，超过了该菱形结构便出现了。显微分析还增强了这些样品的萤石缺陷结构。晶格随着铋的加入而膨胀。样品具有多孔形态，X射线能量色散光谱分析确保了Pr和Bi的存在更接近标称摩尔比。565厘米的强力带由于产生更多的氧空位，随着铋含量的逐渐增加，拉曼光谱中的^-1移至更高的值。X射线光电子能谱分析表明，在Pr _0.60 Bi _0.40 O _{2- δ中}，Pr以+3和+4氧化态存在。光致发光光谱由Pr ³⁺的4f–4f跃迁和蓝色区域的发射（由于氧空位）组成。Pr _0.60 Bi _0.40 O _{2− δ}和PrO _1.833都在取决于磁场和温度的测量中保持低至2 K的顺磁性。从PrO _1.833到Pr _0.60 Bi _0.40 O _{2− δ}移动时，有效磁矩，保持力和矫顽力降低。铋取代的样品催化二甲苯酚橙和甲基橙的氧化降解。鉴定了这些反应的降解产物。铋取代的样品还催化了硝基芳烃的还原。这些转变遵循伪一级动力学。