Porous Ag/TiO2-Schottky-diode based plasmonic hot-electron photodetector with high detectivity and fast response
Gao Xu Dong,
Fei Guang Tao,
Xu Shao Hui,
Zhong Bin Nian,
Ouyang Hao Miao,
Li Xin Hua,
Zhang Li De
Affiliations
Gao Xu Dong
Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical Sciences, Chinese Academy of Sciences, Hefei, Anhui 230031, P.R. China
Fei Guang Tao
Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical Sciences, Chinese Academy of Sciences, Hefei, Anhui 230031, P.R. China
Xu Shao Hui
Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical Sciences, Chinese Academy of Sciences, Hefei, Anhui 230031, P.R. China
Zhong Bin Nian
Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical Sciences, Chinese Academy of Sciences, Hefei, Anhui 230031, P.R. China
Ouyang Hao Miao
Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical Sciences, Chinese Academy of Sciences, Hefei, Anhui 230031, P.R. China
Li Xin Hua
Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical Sciences, Chinese Academy of Sciences, Hefei, Anhui 230031, P.R. China
Zhang Li De
Key Laboratory of Materials Physics and Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, Hefei Institutes of Physical Sciences, Chinese Academy of Sciences, Hefei, Anhui 230031, P.R. China
Due to the advantages of narrow energy distribution of plasmonic hot-electrons in Ag and the high density of states in the TiO2 conduction band, an Ag/TiO2 composite is considered to be an ideal combination to construct a plasmonic hot-electron photodetector with high detectivity and a high response speed. In this work, we fabricate a porous Ag/TiO2-Schottky-diode based plasmonic hot-electron photodetector. This detector shows a high detectivity of 9.8 × 1010 cmHz1/2/W and a fast response speed, with a rise and fall time of 112 μs and 24 μs, respectively, under 450 nm light illumination at zero bias voltage. In addition, the height of the Ag/TiO2 Schottky barrier can be decreased by removing the chemisorbed oxygen from the surface of TiO2 with ultraviolet light illumination, and as a result, the responsivity of the Ag/TiO2 plasmonic hot-electron photodetector at 450 nm can increase from 3.4 mA/W to 7.4 mA/W.
