Highly Enhanced Photocatalytic NO Removal and Inhibited Peroxyacetyl Nitrate Formation in Synergistic Acetaldehyde Degradation.

The coexistence of NO and CHCHO 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 (CHCHO) on SrSbO. In comparison with the single removal, the nearly complete removal of NO is reached by deep oxidation to NO with the assistance of CHCHO. The underlying mechanism is revealed by GC-MS, in situ DRIFTS, and density functional theory calculations. The intermediates CH from CHCHO and NO from NO tend to bond and further oxidize to CHONO, thus promoting NO removal. CHNO and CHONO are the key products instead of PAN on SrSbO from the synergistic degradation of NO and CHCHO. This work brings new insights into reaction pathway regulation for promoting performance and suppressing byproducts during synergistic air pollutant removal.