A high efficiency microreactor with Pt/ZnO nanorod arrays on the inner wall for photodegradation of phenol

Highlights: • A novel microreactor with Pt/ZnO nanorod arrays on the inner wall is fabricated. • The microreactor shows high efficiency for photodegradation of phenol. • The Pt/ZnO nanorod arrays display high durability during continuous recycling. • It provides a new way to immobilize catalysts on the inner wall of a microchannel. -- Abstract: A high efficiency microreactor with Pt coated ZnO (Pt/ZnO) nanorod arrays on the inner wall was successfully fabricated by pumping a Pt sol into the microchannel containing preformed ZnO nanorod arrays. Phenol was selected as a persistent organic pollutant to evaluate the photocatalytic performance of the microreactors. The microreactor which was coated by Pt sol for 5 min showed the best photocatalytic performance compared with other Pt/ZnO nanorod array-modified microreactors. The presence of Pt nanoparticles on the surfaces of ZnO nanorods promoted the separation of photoinduced electron–hole pairs and thus enhanced the photocatalytic activity. In addition, the recyclable property of the microcreator was investigated. It was found that the microreactor displayed higher durability during the continuous photocatalytic process