Abstract Herein, yolk-shell LaFeO3 (YS-LFO) microsphere has been successfully prepared by a carbon microsphere (CMS) template-adsorption-calcination method. It was confirmed that the YS-LFO microspheres showed high visible-light photoactivities for 2,4-dichlorophenol degradation as compared to bare LaFeO3 (LFO) nanoparticles, attributing to the unique yolk-shell structure and the increased surface area. The visible-light photocatalytic activities of YS-LFO microspheres could be further promoted by coupling with SnO2 (SO) nanoparticles. Based on the surface photovoltage spectra, photoelectrochemical measurements and other characterization, it was demonstrated that the coupled SO afforded a thermodynamically suitable platform for accepting the high-level energy electrons from LaFeO3 so as to enhance the charge separation. Compared with YS-LFO microspheres and LFO nanoparticles, the amount optimized (10SO/YS-LFO) nanocomposites displayed 1.6 and 4.7-time enhancement for 2,4-dichlorophenol degradation under visible-light irradiation, respectively. This efficient strategy of morphology controlling and photoelectron modulating could pave the approach to design high-activity visible-light driven photocatalysts.

中文翻译：

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合成 SnO2/蛋黄-壳 LaFeO3 纳米复合材料作为有效的可见光光催化剂降解 2,4-二氯苯酚

摘要 本文采用碳微球（CMS）模板-吸附-煅烧法成功制备了蛋黄-壳LaFeO3（YS-LFO）微球。经证实，与裸露的 LaFeO3 (LFO) 纳米粒子相比，YS-LFO 微球对 2,4-二氯苯酚的降解表现出较高的可见光光活性，这归因于独特的蛋黄-壳结构和增加的表面积。YS-LFO 微球的可见光光催化活性可以通过与 SnO2 (SO) 纳米粒子的偶联得到进一步提高。基于表面光电压谱、光电化学测量和其他表征，表明耦合的 SO 提供了一个热力学合适的平台，用于接受来自 LaFeO3 的高能电子以增强电荷分离。与 YS-LFO 微球和 LFO 纳米粒子相比，优化量的 (10SO/YS-LFO) 纳米复合材料在可见光照射下对 2,4-二氯苯酚的降解分别显示了 1.6 倍和 4.7 倍的增强。这种有效的形态控制和光电子调制策略可以为设计高活性可见光驱动的光催化剂铺平道路。