Actinomorphic flower-like n-ZnO/p-ZnFe2O4 composite and its improved NO2 gas-sensing property

Actinomorphic flower-like ZnO/ZnFe2O4 composite has been successfully synthesized by a facile two-step synthesis method. The as-prepared samples have been characterized by XRD, SEM and TEM. Compared with pure-ZnO sensor, the ZnO/ZnFe2O4-based sensor exhibited remarkably higher response, shorter response-recovery time and more superior selective to low-concentration NO2 at low operating temperature of 200 °C. The mechanism of enhanced gas-sensing performance of the ZnO/ZnFe2O4 composite with p-n heterostructure has been investigated. It indicates that the as-prepared ZnO/ZnFe2O4 composite is promising for NO2 gas sensor.