Abstract This study demonstrates a one-step hydrothermal approach to prepare novel spherical microstructures of Mn-doped TiO2 by the in situ template-sacrificial conversion of MnCO3 microspheres grown in a radial direction. After a hydrothermal reaction, MnCO3 microspheres were completely dissolved by HF as a hydrolysis product of [NH4]2TiF6. Furthermore, the hollow and radially porous structures of Mn-doped TiO2 microspheres were obtained without and with stirring during hydrothermal reaction, respectively. The prepared anatase TiO2 microspheres were fully characterized in terms of particle size, morphology, chemical composition, and porosity by X-ray diffraction, scanning and transmission electron microscopies, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller method, respectively. The photocatalytic activity of the prepared TiO2 microspheres was evaluated by the degradation of methylene blue under UV and visible light irradiations. Our versatile approach can be used for different types of metal carbonates to fabricate morphology controllable metal oxide nano- and microstructures.

中文翻译：

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MnCO3 微球的模板牺牲转化制备 Mn 掺杂的 TiO2 可见光光催化剂

摘要 本研究展示了一种一步水热法，通过对径向生长的 MnCO3 微球进行原位模板-牺牲转化来制备 Mn 掺杂的 TiO2 的新型球形微结构。水热反应后，MnCO3 微球被 HF 完全溶解，成为 [NH4]2TiF6 的水解产物。此外，在水热反应过程中，分别在没有和有搅拌的情况下获得了Mn掺杂的TiO2微球的空心和径向多孔结构。通过X射线衍射、扫描和透射电子显微镜、X射线光电子能谱和Brunauer-Emmett-Teller方法分别对制备的锐钛矿TiO2微球的粒度、形貌、化学组成和孔隙率进行了全面表征。通过紫外光和可见光照射下亚甲基蓝的降解来评价制备的TiO2微球的光催化活性。我们的通用方法可用于不同类型的金属碳酸盐，以制造形态可控的金属氧化物纳米和微结构。