Highly Enhanced Photocatalytic NO Removal and Inhibited Peroxyacetyl Nitrate Formation in Synergistic Acetaldehyde Degradation
Ting Xue, Lvcun Chen, Kanglu Li, Ben Lei, Hong Wang, Fan Dong, Yan Yang
Abstract
The coexistence of NO and CH 3 CHO in the air is considered to produce secondary peroxyacetyl nitrate (PAN) under sunlight irradiation, threatening the ecological environment and public health. Herein, we provide a simple strategy for the photocatalytic removal of NO and acetaldehyde (CH 3 CHO) on Sr 2 Sb 2 O 7 . In comparison with the single removal, the nearly complete removal of NO is reached by deep oxidation to NO 3 – with the assistance of CH 3 CHO. The underlying mechanism is revealed by GC–MS, in situ DRIFTS, and density functional theory calculations. The intermediates • CH 3 from CH 3 CHO and NO 2 – from NO tend to bond and further oxidize to CH 3 ONO 2, thus promoting NO removal. CH 3 NO 2 and CH 3 ONO 2 are the key products instead of PAN on Sr 2 Sb 2 O 7 from the synergistic degradation of NO and CH 3 CHO. This work brings new insights into reaction pathway regulation for promoting performance and suppressing byproducts during synergistic air pollutant removal.