Zhao Kun, Ouyang Bangsen, Yang Ya
CAS Center for Excellence in Nanoscience, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, P. R. China; School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
CAS Center for Excellence in Nanoscience, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, P. R. China; School of Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
iScience. 2018 May 25;3:208-216. doi: 10.1016/j.isci.2018.04.016. Epub 2018 Apr 25.
The pyro-phototronic effect has been utilized to modulate photoexcited carriers, to enhance the photocurrent in semiconducting nanomaterials. However, most of these materials have low pyroelectric performances. Using radially polarized ferroelectric BaTiO materials with a pyroelectric coefficient of about 16 nC/cmK, we report a dramatic photocurrent enhancement due to ferro-pyro-phototronic effect. The fabricated device enables a fast sensing of 365-nm light illumination with a response time of 0.5 s at the rising edge, where the output current-time curve displays a sharp peak followed by a stable plateau. By applying a heating temperature variation, the output current peak can be enhanced by more than 30 times under a light intensity of 0.6 mW/cm. Moreover, the stable current plateau can be enhanced by 23% after utilizing a cooling temperature variation, which can be well explained by ferro-pyro-phototronic-effect-induced energy band bending.
热光电子效应已被用于调制光激发载流子，以增强半导体纳米材料中的光电流。然而，这些材料大多具有较低的热释电性能。我们使用热释电系数约为16 nC/cmK的径向极化铁电体BaTiO材料，报道了由于铁热电光电子效应导致的显著光电流增强。所制备的器件能够快速检测365 nm光照明，上升沿的响应时间为0.5 s，输出电流-时间曲线显示出一个尖锐的峰值，随后是一个稳定的平台。通过施加加热温度变化，在0.6 mW/cm的光强度下，输出电流峰值可提高30倍以上。此外，利用冷却温度变化后，稳定电流平台可提高23%，这可以通过铁热电光电子效应引起的能带弯曲得到很好的解释。
