Abstract Using simple solid state reaction route, the La and Fe doped SrTiO3 nanoparticle have been successfully synthesized. The effects of different dopant concentrations (1, 2, 3, 4 and 5 wt %) on the characteristics of the as-prepared samples were systematically investigated using various techniques. X-ray diffraction (XRD) investigation exhibit the formation of the cubic perovskite structure of all samples. Field emission scanning electron microscopy (FESEM) images have been confirmed the uniformity and particle size reduction of the samples with increasing of doping elements. Also, the increase of surface area from 9.7 m2/g for pure SrTiO3 to 64.2 m2/g for 5 wt% La-Fe doped SrTiO3 validated by Brunauer-Emmett-Teller (BET) studies. The UV–vis diffuse reflectance spectra (DRS) demonstrate the blue-shift of absorption tail for doped samples as well as reduction of band gap energies (from 3.2 eV to 2.72 eV) with the increase of the doped element. Photoluminescence (PL) analysis of the synthesis nanoparticle display defective states and decline in PL intensity as a result of the doping materials effect in SrTiO3. The 150 min of irradiation time, 0.6 g/L of catalyst dosage, and 5 ppm of initial MO concentration have been obtained as the optimum photocatalyst operating conditions. Also, the photocatalytic investigation reveals the enhancement of degradation rate of Methyl Orange (MO) under visible irradiation for the doped sample. The perfect photocatalytic activity at 4 wt% of Fe-La-doped SrTiO3 nanoparticles is around 19 times higher than that of pure SrTiO3 (96% compare to 5%). In the end, the photocatalytic performance mechanisms are deeply explained.

中文翻译：

---

La-Fe共掺杂SrTiO3钙钛矿粉体的可见光光催化性能

摘要 采用简单的固相反应途径，成功合成了La和Fe掺杂的SrTiO3纳米颗粒。使用各种技术系统地研究了不同掺杂剂浓度（1、2、3、4 和 5 重量％）对所制备样品特性的影响。X 射线衍射 (XRD) 研究表明，所有样品都形成了立方钙钛矿结构。场发射扫描电子显微镜 (FESEM) 图像已经证实，随着掺杂元素的增加，样品的均匀性和粒度减小。此外，Brunauer-Emmett-Teller (BET) 研究验证了表面积从纯 SrTiO3 的 9.7 m2/g 增加到 5 wt% La-Fe 掺杂 SrTiO3 的 64.2 m2/g。UV-vis 漫反射光谱 (DRS) 表明掺杂样品的吸收尾部蓝移以及带隙能量随着掺杂元素的增加而降低（从 3.2 eV 到 2.72 eV）。由于 SrTiO3 中的掺杂材料效应，合成纳米颗粒的光致发光 (PL) 分析显示出缺陷状态和 PL 强度下降。150 min 的辐照时间、0.6 g/L 的催化剂用量和 5 ppm 的初始 MO 浓度已被确定为最佳光催化剂操作条件。此外，光催化研究揭示了掺杂样品在可见光照射下甲基橙（MO）的降解速率的提高。Fe-La 掺杂的 SrTiO3 纳米粒子在 4 wt% 时的完美光催化活性比纯 SrTiO3 高约 19 倍（96% 与 5% 相比）。