ZnO nanorods grown on polymer substrates as UV photodetectors

Abstract

Vertical well-aligned and uniform ZnO nanorods were successfully prepared on low cost and flexible PET polymer substrate by aqueous solution method under various growth conditions. Current-voltage (I-V) and current-time (I-t) relationships measurements demonstrate that the photocurrent can be increased by more than 25 times upon UV illumination (lambda = 365 nm) with a power density of 70 mu W/cm(2). The photocurrents can be repeatedly and reproducibly switched by modulating UV exposure with power densities of 25-70 mu W/cm(2). The fast response time (100s) and rapid recovery time (120s) are achieved in UV turn-on/off switching measurements. Owing to the good performance including mechanical flexibility, nondestructive properties, high reliability and multilevel photoresponse, the well-aligned ZnO nanorods grown on transparent and flexible PET polymer substrates have high potential for UV photodetector applications. (C) 2012 Elsevier B.V. All rights reserved.