Chinese Journal of Catalysis ›› 2016, Vol. 37 ›› Issue (1): 27-31.DOI: 10.1016/S1872-2067(15)61026-9

• Special Column on New Porous Catalytic Materials • Previous Articles     Next Articles

Synthesis of three-dimensional ordered mesoporous MnO2 and its catalytic performance in formaldehyde oxidation

Bingyang Baia,b, Qi Qiaoa,b, Junhua Lic, Jiming Haoc   

  1. a State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China;
    b Key Laboratory of Eco-Industry of the Ministry of Environmental Protection, Chinese Research Academy of Environmental Sciences, Beijing 100012, China;
    c State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
  • Received:2015-05-28 Revised:2015-07-07 Online:2015-12-26 Published:2015-12-26
  • Supported by:

    This work was supported by the National Natural Science Foundation of China (21325731, 21221004 and 51478241).

Abstract:

Three-dimensional (3D) ordered mesoporous MnO2 was prepared using KIT-6 mesoporous molecular sieves as a hard template. The material was used for catalytic oxidation of HCHO. The material has high surface areas and the mesoporous characteristics of the template, with cubic symmetry (ia3d). It consists of a β-MnO2 crystalline phase corresponding to pyrolusite, with a rutile structure. Transmission electron microscopy and X-ray photoelectron spectroscopy showed that the 3D-MnO2 catalyst has a large number of exposed Mn4+ ions on the (110) crystal plane surfaces, with a lattice spacing of 0.311 nm; this enhances oxidation of HCHO. Complete conversion of HCHO to CO2 and H2O was achieved at 130 ℃ on 3D-MnO2; the same conversions on α-MnO2 and β-MnO2 nanorods were obtained at 140 and 180 ℃, respectively, under the same conditions. The specific mesoporous structure, high specific surface area, and large number of surface Mn4+ ions are responsible for the catalytic activity of 3D-MnO2 in HCHO oxidation.

Key words: Three-dimensional ordered material, Mesoporous structure, Manganese oxide, Formaldehyde, Catalytic oxidation