Abstract
High-performance photocatalytic and photoresponsive properties have been made from composite ZnSnO 3 nanowires. The composite nanowires consist of several phases, such as a major phase of ZnSnO 3 and second phases of ZnO, SnO 2 , and metallic Zn nanowires. These nanowires formed many nanowire-to-nanowire junctions at the networking points of the ZnO/ZnSnO 3 /SnO 2 interfaces; thus, a heterojunction cascade is obtained in the presence of these semiconductors. A charge transfer takes place at the composite nanowires under UV-light (λ ∼ 365 nm, I = 2.33 mWcm -2 ), and the Zn nanowires subsequently act as effective electron collectors, resulting in an extremely high photocurrent under an Ohmic contact electrode. The photoelectric current of the composite ZnSnO 3 nanowires exhibited a rapid photoresponse of ∼1 sec upon irradiation by UV light. An extremely high photo-current to dark-current ratio is 2.7 × 10 5 %. The composite nanowires exhibited an extremely high photodegradation ratio of ∼66% within 30 minutes under UV-light irradiation. Photocatalysts of composite ZnSnO 3 nanowires were found to be superior to those made from composite ZnO-SnO 2 , ZnO, and SnO 2 nanowires. The ZnSnO 3 nanowires successfully acted as key components of the photoexcited separation and migration of the generated charges with a low recombination rate. © 2012 The Electrochemical Society.