Highly active Ag/ZnO/ZnAl-LDH heterojunction photocatalysts for NO removal

Development of effective photocatalytic technologies to control low concentration NO pollutant is of fundamental and technological significance, and improving charge separation and surface activity are the crucial issues to be solved. In this work, we design an in-situ method to construct ZnO loaded ZnAl-LDH heterojunction with metallic Ag co-modified. The optimal catalyst displays a photocatalytic performance with the NO removal ratio of 80.0%, meanwhile, the toxic NO2 generation can be significantly inhibited. This high activity could be attributed to the formation of a Ag/ZnO/ZnAl-LDH heterojunction that could promote the charge separation and transfer. Meanwhile, the unique property of Ag nanoparticle with the localized surface plasmonic resonance (LSPR), which increases the light absorption capacity of the catalyst and accelerates the charge transfer from ZnO to ZnAl-LDH via Ag nanoparticle as the electron transfer channel. This work can provide a novel co-modification strategy for efficient carriers transfer, and bring forward deep insights into the interfacial reaction mechanism of photocatalytic NO oxidation.