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Sodium Rivals Silver as Single-Atom Active Centers for Catalyzing Abatement of Formaldehyde
journal contribution
posted on 2017-05-24, 00:00 authored by Yaxin Chen, Jiayi Gao, Zhiwei Huang, Meijuan Zhou, Junxiao Chen, Chao Li, Zhen Ma, Jianmin Chen, Xingfu TangThe development of efficient alkali-based
catalysts for the abatement
of formaldehyde (HCHO), a ubiquitous air pollutant, is economically
desirable. Here we comparatively study the catalytic performance of
two single-atom catalysts, Na1/HMO and Ag1/HMO
(HMO = Hollandite manganese oxide), in the complete oxidation of HCHO
at low temperatures, in which the products are only CO2 and H2O. These catalysts are synthesized by anchoring
single sodium ions or silver atoms on HMO(001) surfaces. Synchrotron
X-ray diffraction patterns with structural refinement together with
transmission electron microscopy images demonstrate that single sodium
ions on the HMO(001) surfaces of Na1/HMO have the same
local structures as silver atoms of Ag1/HMO. Catalytic
tests reveal that Na1/HMO has higher catalytic activity
in low-temperature oxidation of HCHO than Ag1/HMO. X-ray
photoelectron spectra and soft X-ray absorption spectra show that
the surface lattice oxygen of Na1/HMO has a higher electronic
density than that of Ag1/HMO, which is responsible for
its higher catalytic efficiency in the oxidation of HCHO. This work
could assist the rational design of cheap alkali metal catalysts for
controlling the emissions of volatile organic compounds such as HCHO.