Enhanced formaldehyde oxidation on Pt/MnO₂ catalysts modified with alkali metal salts

Ying Chen; Junhui He; Hua Tian; Donghui Wang; Qiaowen Yang

doi:10.1016/j.jcis.2014.04.028

Enhanced formaldehyde oxidation on Pt/MnO₂ catalysts modified with alkali metal salts

J Colloid Interface Sci. 2014 Aug 15:428:1-7. doi: 10.1016/j.jcis.2014.04.028. Epub 2014 Apr 24.

Authors

Ying Chen¹, Junhui He², Hua Tian³, Donghui Wang⁴, Qiaowen Yang⁵

Affiliations

¹ Functional Nanomaterials Laboratory and Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences (CAS), Beijing 100190, China; School of Chemical and Environmental Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China.
² Functional Nanomaterials Laboratory and Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences (CAS), Beijing 100190, China. Electronic address: jhhe@mail.ipc.ac.cn.
³ Functional Nanomaterials Laboratory and Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences (CAS), Beijing 100190, China.
⁴ Research Institute of Chemical Defense, Beijing 100083, China.
⁵ School of Chemical and Environmental Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China.

PMID: 24910027
DOI: 10.1016/j.jcis.2014.04.028

Abstract

Novel Pt/MnO2 catalysts modified with alkali metal salts were prepared and exhibited excellent catalytic activity for formaldehyde oxidation. The effects of both cation and anion in the salts were investigated on the structure of catalysts and their catalytic activity. The Na(+) modification was demonstrated to be a facile and effective method to improve the catalysts performance for formaldehyde oxidation, but the anions remaining on the support might act as a mild poison by covering the surface active sites of manganese oxides. The enhancing effect of anions in the salts follows the order of CO3(2-)>SO4(2-)>NO3(-). A 100% formaldehyde conversion can be obtained at 50°C over the Na2CO3-modified catalyst. Further analyses indicate that strong metal-support interaction, well-dispersed Pt nanoparticles with small particle sizes and large surface area are important for high catalytic activity.

Keywords: Alkali metal salts; Formaldehyde oxidation; Manganese oxide; Platinum nanoparticle.