超小尺寸碳载Mn3O4纳米催化剂制备及其高效降解亚甲基蓝

Preparation of ultrafine carbon-supported Mn3O4 nanocatalyst for efficient degradation of methylene blue

摘要:

将聚乙二醇（PVA）作为稳定剂，介导沉淀法制备Mn3O4纳米粒子，制备了超小尺寸的Mn3O4-C催化剂。使用XRD、XPS、TEM表征制备的材料的结构和形貌，发现PVA能够有效减小Mn3O4的聚集和长大。制备过程中PVA分子链间的Mn3O4纳米粒子尺寸为3.2（±0.8） nm，经过Ar保护碳化处理后，尺寸为4.5（±1.2 nm的Mn3O4纳米粒子被均匀的固定在C基底上。制备的Mn3O4-C催化剂具有高效的类芬顿催化降解亚甲基蓝的能力。同时，相较于无PVA介导沉淀法制备的Mn3O4纳米粒子，Mn3O4-C具有更好的循环稳定性。

Abstract:

A ultrafine carbon-supported Mn3O4 nanocatalyst by poly (vinyl alcohol)(PVA) mediated precipitation method using poly(ethylene glycol) (PVA) as a stabiliser was reported. The structure and morphology of the prepared nanomaterials were characterized by XRD, XPS, and TEM, and it was found that PVA could effectively reduce the aggregation and growth of Mn3O4 nanoparticles during the preparation process. The size of Mn3O4 nanoparticles prepared in the absence of PVA is 38.8 (±9.3) nm, while the size of Mn3O4 nanoparticles dispersed in the PVA molecular chains was 3.2 (±0.8) nm. After the Ar-protected carbonization treatment of the freeze-dried PVA/Mn3O4 composite, the Mn3O4 nanoparticles were uniformly immobilized on the C substrate with a particle size of 4.5 (±1.2) nm. The prepared Mn3O4-C catalysts have excellent ability for Fenton-like degradation of methylene blue (MB). Meanwhile, Mn3O4-C has better cycling stability compared to the Mn3O4 nanoparticles prepared in the absence of PVA.