Dung Nguyen Trung, Thu Tran Viet, Van Nguyen To, Thuy Bui Minh, Hatsukano Masahito, Higashimine Koichi, Maenosono Shinya, Zhong Ziyi
Department of Chemical Engineering, Le Quy Don Technical University 236 Hoang Quoc Viet Hanoi 100000 Vietnam
Institute of Research and Development, Duy Tan University Da Nang 550000 Vietnam.
RSC Adv. 2020 Jan 22;10(7):3775-3788. doi: 10.1039/c9ra10169a.
In this work, we report the facile hydrothermal synthesis of manganese cobaltite nanoparticles (MnCoO NPs) which can efficiently activate peroxymonosulfate (PMS) for the generation of sulfate free radicals (SO˙) and degradation of organic dyes. The synthesized MnCoO NPs have a polyhedral morphology with cubic spinel structure, homogeneously distributed Mn, Co, and O elements, and an average size less than 50 nm. As demonstrated, MnCoO NPs showed the highest catalytic activity among all tested catalysts (MnO, CoO) and outperformed other spinel-based catalysts for Methylene Blue (MB) degradation. The MB degradation efficiency reached 100% after 25 min of reaction under initial conditions of 500 mg L Oxone, 20 mg L MnCoO, 20 mg L MB, unadjusted pH, and = 25 °C. MnCoO NPs showed a great catalytic activity in a wide pH range (3.5-11), catalyst dose (10-60 mg L), Oxone concentration (300-1500 mg L), MB concentration (5-40 mg L), and temperature (25-55 °C). HCO , CO and particularly Cl coexisting anions were found to inhibit the catalytic activity of MnCoO NPs. Radical quenching experiments revealed that sulfate radicals are primarily responsible for MB degradation. A reaction sequence for the catalytic activation of PMS was proposed. The as-prepared MnCoO NPs could be reused for at least three consecutive cycles with small deterioration in their performance due to low metal leaching. This study suggests a facile route for synthesizing MnCoO NPs with high catalytic activity for PMS activation and efficient degradation of organic dyes.
在本工作中，我们报道了一种简便的水热合成法来制备锰钴矿纳米颗粒（MnCoO NPs），该纳米颗粒能够高效激活过一硫酸盐（PMS）以产生硫酸根自由基（SO˙）并降解有机染料。合成的MnCoO NPs具有立方尖晶石结构的多面体形态，Mn、Co和O元素均匀分布，平均尺寸小于50 nm。结果表明，MnCoO NPs在所有测试催化剂（MnO、CoO）中表现出最高的催化活性，并且在亚甲基蓝（MB）降解方面优于其他基于尖晶石的催化剂。在500 mg L过硫酸氢钾、20 mg L MnCoO、20 mg L MB、未调节pH值以及 = 25 °C的初始条件下反应2五分钟后，MB降解效率达到100%。MnCoO NPs在较宽的pH范围（3.5 - 11）、催化剂剂量（10 - 60 mg L）、过硫酸氢钾浓度（300 - 1500 mg L）、MB浓度（5 - 40 mg L）和温度（25 - 55 °C）下均表现出很高的催化活性。发现共存阴离子HCO 、CO 尤其是Cl会抑制MnCoO NPs的催化活性。自由基猝灭实验表明，硫酸根自由基是MB降解的主要原因。提出了PMS催化活化的反应序列。所制备的MnCoO NPs可重复使用至少三个连续循环，由于金属浸出率低，其性能仅有轻微下降。本研究提出了一种简便的路线来合成具有高催化活性的MnCoO NPs，用于PMS活化和有机染料的高效降解。
