The present investigations deals with the fabrication of metal ion (M = Co+2, Ni+2, and Cu+2) doped-In2O3 photocatalysts by a simple solution combustion method. All the synthesized materials were characterized for different features by various techniques including XRD, FESEM, EDX, XPS, UVDRS, and PL. Synthesized compounds were examined for the degradation of two organic pollutants; cationic dye Rhodamine B (RhB) and pesticide Triclopyr (TC). Modification with metal ions significantly improved the degradation efficiency of pure In2O3 photocatalyst and followed the trend Co+2/In2O3 > Ni+2/In2O3 > Cu+2/In2O3 > In2O3. Highest degradation efficiencies of 99.03% for RhB and 95.84 % for TC were obtained in the case of Co+2/In2O3 (1 mol %) under visible light illumination. Further, Density Functional Theory investigations show that Co+2/In2O3 is the most favorable energetically and leads to the creation of two transition states -as opposed to a single transition state in the other doped systems-, one of which is near the Fermi level and the other at around 1.5 eV above it. We believe that this exclusive property is behind the highest photocatalytic efficiency observed experimentally. Additionally, the doped nanostructures lead to higher visible light absorption and separation of light induced charge carriers. The effect of the pH and the reactive oxygen species were also examined. Besides, a probable mechanism of charge transfer and degradation of the pollutants was presented.

中文翻译：

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Co+2、Ni+2、Cu+2 掺杂氧化铟作为可见的活性纳米光催化剂：一种简单的溶液燃烧合成、DFT 方法的电子能带结构分析以及 RhB 和三氯吡嘧啶的光催化去污


本研究涉及通过简单的固溶燃烧法制备金属离子（M = Co+2、Ni+2 和 Cu+2）掺杂的 In2O3 光催化剂。通过 XRD、FESEM、EDX、XPS、UVDRS 和 PL 等各种技术对所有合成材料的不同特征进行了表征。检查了合成化合物对两种有机污染物的降解;阳离子染料罗丹明 B （RhB） 和农药三氯吡喃 （TC）。金属离子改性显著提高了纯 In2O3 光催化剂的降解效率，并遵循了 Co+2/In2O3 > Ni+2/In2O3 > Cu+2/In2O3 > In2O3 的趋势。在可见光照射下，Co+2/In2O3 （1 mol%） 对 RhB 和 TC 的降解效率最高，分别为 99.03% 和 95.84%。此外，密度泛函理论研究表明，Co+2/In2O3 在能量上是最有利的，并导致产生两个过渡态——而不是其他掺杂系统中的单一过渡态——其中一个接近费米能级，另一个高于费米能级约 1.5 eV。我们相信，这种独特的特性是实验观察到的最高光催化效率的背后原因。此外，掺杂的纳米结构导致更高的可见光吸收和光诱导载流子的分离。还检查了 pH 值和活性氧的影响。此外，还提出了一种电荷转移和污染物降解的可能机制。