Dark Current Reduction Strategy via a Layer-By-Layer Solution Process for a High-Performance All-Polymer Photodetector

Zhiming Zhong; Laju Bu; Peng Zhu; Tong Xiao; Baobing Fan; Lei Ying; Guanghao Lu; Gang Yu; Fei Huang; Yong Cao

doi:10.1021/acsami.8b20981

Dark Current Reduction Strategy via a Layer-By-Layer Solution Process for a High-Performance All-Polymer Photodetector

ACS Appl Mater Interfaces. 2019 Feb 27;11(8):8350-8356. doi: 10.1021/acsami.8b20981. Epub 2019 Feb 12.

Authors

Zhiming Zhong¹, Laju Bu², Peng Zhu¹, Tong Xiao², Baobing Fan¹, Lei Ying¹, Guanghao Lu², Gang Yu¹, Fei Huang¹, Yong Cao¹

Affiliations

¹ Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , China.
² School of Science and Frontier Institute of Science and Technology , Xi'an Jiaotong University , Xi'an 710049 , China.

PMID: 30697994
DOI: 10.1021/acsami.8b20981

Abstract

The ideal bulk-heterojunction for high-performance organic photodetectors prefers a morphology with a vertically gradient component to suppress the leaking current. Here, we demonstrate an all-polymer photodetector with a segregated bulk-heterojunction active layer. This all-polymer photodetector exhibits a dramatically reduced dark current density because of its built-in charge blocking layer, with a responsivity of 0.25 A W^-1 at a wavelength of approximately 600 nm and specific detectivity of 5.68 × 10¹² cm Hz^1/2 W^-1 as calculated from the noise spectra at 1 kHz. To our knowledge, this is among the best performances reported for photodetectors based on both polymeric donor and acceptor in the photoactive layer. These findings present a facile approach to improving the specific detectivity of polymer photodetectors via a layer-by-layer solution process.

Keywords: all-polymer photodetector; gradient bulk heterojunction; imide functionalized benzotriazole; layer-by-layer process; noise spectral density.