Xu Yaohui, Ding Zhao
Laboratory for Functional Materials, School of New Energy Materials and Chemistry, Leshan Normal University, Leshan 614004, China.
College of Materials Science and Engineering, National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044, China.
Materials (Basel). 2022 Jul 27;15(15):5209. doi: 10.3390/ma15155209.
Hydrogen peroxide (HO), an accessible and eco-friendly oxidant, was employed for the template-free hydrothermal synthesis of mesoporous CeO based on a cerium carbonate precursor (Ce(CO)•HO). Its microstructure and physicochemical properties were characterized by XRD, TEM and N sorption techniques. The formation of the CeO phase with a porous structure was strongly dependent on the presence of HO, while the values of the BET surface area, pore diameter and pore volume of CeO were generally related to the amount of HO in the template-free hydrothermal synthesis. The BET surface area and pore volume of the mesoporous CeO synthesized hydrothermally at 180 °C with 10 mL HO were 112.8 m/g and 0.1436 cm/g, respectively. The adsorption process had basically finished within 30 min, and the maximum adsorption efficiency within 30 min was 99.8% for the mesoporous CeO synthesized hydrothermally at 140 °C with 10 mL, when the initial AO7 concentration was 120 mg/L without pH preadjustment. The experimental data of AO7 adsorption were analyzed using the Langmuir and Freundlich isotherm modes. Moreover, the mesoporous CeO synthesized at 140 °C with 10 mL HO was regenerated in successive adsorption-desorption cycles eight times without significant loss in adsorption capacity, suggesting that the as-synthesized mesoporous CeO in this work was suitable as an adsorbent for the efficient adsorption of AO7 dye from an aqueous solution.
过氧化氢（HO）是一种易得且环保的氧化剂，基于碳酸铈前驱体（Ce(CO)•HO）用于介孔CeO的无模板水热合成。通过XRD、TEM和N吸附技术对其微观结构和物理化学性质进行了表征。具有多孔结构的CeO相的形成强烈依赖于HO的存在，而CeO的BET表面积、孔径和孔体积值通常与无模板水热合成中HO的量有关。在180°C下用10 mL HO水热合成的介孔CeO的BET表面积和孔体积分别为112.8 m/g和0.1436 cm/g。吸附过程在30分钟内基本完成，当初始AO7浓度为120 mg/L且未进行pH预调节时，在140°C下用10 mL水热合成的介孔CeO在30分钟内的最大吸附效率为99.8%。使用Langmuir和Freundlich等温线模型对AO7吸附的实验数据进行了分析。此外，在140°C下用10 mL HO合成的介孔CeO在连续的吸附-解吸循环中再生了八次，吸附容量没有明显损失，这表明本文中合成的介孔CeO适合作为从水溶液中高效吸附AO7染料的吸附剂。
