College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, PR China.
College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, PR China.
J Colloid Interface Sci. 2019 Mar 15;539:65-75. doi: 10.1016/j.jcis.2018.12.061. Epub 2018 Dec 17.
Boosting total oxidation of volatile organic compounds (VOCs) over spinel CoO by cation-substituting effect is an effective solution, but the underlying mechanism has not yet been clearly elucidated. Herein, a series of spinel MCoO (M = Co, Ni, Cu) hollow mesoporous spheres (HMS) have been synthesized by solvothermal alcoholysis with goals to elaborate the cation-substituting effect on spinel CoO for total oxidation of VOCs. The physicochemical properties of spinel MCoO (M = Co, Ni, Cu) HMS have been well characterized and correlated with their catalytic activities. Results reveal that CuCoO HMS exhibited superior catalytic activity than those of NiCoO and CoCoO HMS for total oxidation of acetone and their catalytic activities followed the sequence of CuCoO > NiCoO > CoCoO. This phenomenon can be attributed to the cation-substituting effect, which resulted in the synthesized catalysts with different amounts of surface Co cations, active oxygen species, defective sites and reducible capabilities. Meanwhile, kinetics studies offer direct evidence to support that the cation-substituting effect played the decisive role in determining the catalytic activity, and the underlying mechanism has been proposed by correlating the structure-activity relationship. Moreover, CuCoO HMS also showed excellent long-term stability and good water tolerance due to its highly stable crystal phase and robust morphological structure, demonstrating its potential applications in the field of VOCs elimination.
通过阳离子取代效应来提高挥发性有机化合物（VOCs）的总氧化效率是一种有效的解决方案，但其中的底层机制尚未得到明确的阐述。在此，我们通过溶剂热醇解合成了一系列尖晶石 MCoO（M=Co、Ni、Cu）中空介孔球（HMS），旨在详细研究阳离子取代效应对尖晶石 CoO 进行 VOCs 完全氧化的影响。我们对尖晶石 MCoO（M=Co、Ni、Cu）HMS 的物理化学性质进行了充分的表征，并将其与催化活性相关联。结果表明，CuCoO HMS 对丙酮的完全氧化表现出优于 NiCoO 和 CoCoO HMS 的催化活性，其催化活性顺序为 CuCoO > NiCoO > CoCoO。这种现象可归因于阳离子取代效应，它导致合成的催化剂具有不同数量的表面 Co 阳离子、活性氧物种、缺陷位和还原能力。同时，动力学研究提供了直接证据，支持阳离子取代效应对决定催化活性起决定性作用，并且通过关联结构-活性关系提出了潜在的机制。此外，由于其高度稳定的晶体相和坚固的形态结构，CuCoO HMS 还表现出优异的长期稳定性和良好的耐水性，展示了其在 VOCs 消除领域的潜在应用。
