High-performance flexible ultraviolet photoconductors based on solution-processed ultrathin ZnO/Au nanoparticle composite films

摘要

Transparent ultraviolet (UV) ZnO thin film photoconductors are expected to have great applications in environmental monitoring, large-area displays, and optical communications, and they have drawn enormous interests in recent years. However, at present their performances are not satisfactory: the responsivity R (a parameter characterizing the sensitivity of the device to light) is not high (<1.0 × 10³ AW⁻¹), and the transparency T is not high either (<80%). Realizing high R and high T remains a big challenge today. In this paper, by employing solution-processed ultrathin ZnO/Au nanoparticle composite films, R as high as 1.51 × 10⁵ AW⁻¹ and T of over 90% are achieved. High values for detectivity D* and linear dynamic range LDR are also obtained, which are 2.05 × 10¹⁵ Jones and 60 dB, respectively. Moreover, such high-performance devices can be fabricated on flexible PET (polyethylene terephthalate) substrates.