Fluorination-enhanced photoconductive effect in a wide band gap Ca3Ti2O7-xFx thin films
Fluorination-enhanced photoconductive effect in a wide band gap Ca3Ti2O7-xFx thin films
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宽带隙 Ca3Ti2O7-xFx 薄膜中的氟化增强光电导效应
DOI：
10.1088/2053-1591/abd0a4
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发表时间：
2020
影响因子：
2.3
通讯作者：
Gao Ju
中科院分区：
文献类型：
--
作者：
Lu Hao;Yang Yang;Luo Zhongshen;Wu Sihui;Ji Y;a;Li Yang;Zhang Jinlei;Liu Guozhen;Jiang Yucheng;Yang Hao;Ma Chunlan;Zhao Run;Gao Ju
在这项工作中，(110) SrTiO 3 基底上的Ca 3 Ti 2 O 7-x F x 薄膜通过脉冲激光沉积和聚偏氟乙烯氟化两个步骤制备。尽管氟化薄膜的晶体结构没有改变，但价态的变化可以用来证实F−1的结合和Ca-O化学键的减弱。此外，我们发现光电开关可以在405 nm至808 nm的宽范围光波长下观察到。研究发现，氟中4×10 4 (405 nm)的光敏度提高了两个数量级，这很可能是由于带隙减小至2.3 eV时的深能级所致。这项工作为通过阴离子缺陷工程增强光电导器件铺平了道路。
In this work, Ca 3 Ti 2 O 7-x F x thin films on (110) SrTiO 3 substrates were prepared by two steps as deposited via pulsed laser deposition and fluorinated with polyvinylidene fluoride. Despite the unchanged crystal structure of the fluorinated films, the changed valence state can be used to confirm the incorporation of F− 1 and the weakened chemical bond of Ca–O. Furthermore, we found that the photoelectric switch can be observed at a wide range of light wavelength from 405 nm to 808 nm. It is found that the photosensitivity of 4× 10 4 (405 nm) in the fluorine has been increased by two orders of magnitude, which is most likely due to the deep energy levels in the reduced band gap of 2.3 eV. This work paves the way for the enhanced photoconductive devices via the anionic defect engineering.