Plasmon-Assisted Polarity Switching of a Photoelectric Conversion Device by UV and Visible Light Irradiation
Plasmon-Assisted Polarity Switching of a Photoelectric Conversion Device by UV and Visible Light Irradiation
复制标题
紫外与可见光照射下光电转换器件的等离激元辅助极性切换
DOI：
10.1021/acs.jpcc.8b01198
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发表时间：
2018-06-28
影响因子：
3.7
通讯作者：
Misawa, Hiroaki
中科院分区：
文献类型：
--
作者：
Nakamura, Keisuke;Oshikiri, Tomoya;Misawa, Hiroaki
作为等离子体光能转换器件的机理之一，等离子体激元诱导纳米金属粒子与半导体之间的电荷分离已经被广泛地研究。在本研究中，我们提出了通过改变等离子体光电转换器件的整流特性和利用电子和空穴之间载流子迁移率的差异来实现光电流极性的切换。我们利用金纳米颗粒(Au-NPs)、氧化镍(NiO)和迁移率受限的二氧化钛(ML-Ti02)制备了等离子体光电转换器件，以根据可见光和紫外光的照射波长来控制光电流的极性。采用脉冲激光沉积技术沉积ML-TiO2层和NiO层。测量了Au-NPs的光电性质，并进行了原位光谱电化学测试，研究了紫外光照射下Au-NPs的费米能级变化与等离子体光电转换器件整流特性的关系。此外，紫外光和可见光照射可以在较小的外加电压下选择性地诱导出极性相反的电流。从ML-Ti02到Au-NPs以及从Au-NPs到ML-Ti02的电子转移现象为我们理解等离子体相关电荷分离提供了重要信息。
The plasmon-induced charge separation between metallic nanoparticles and a semiconductor following an electron transfer process has been extensively studied as one of the mechanisms in plasmonic light energy conversion devices. In this study, we propose that the switching of photocurrent polarity can be realized by changing the rectification properties of plasmonic photoelectric conversion devices and utilizing the difference in carrier mobility between electrons and holes. We fabricated plasmonic photoelectric conversion devices using gold nanoparticles (Au-NPs), nickel oxide (NiO), and mobility-limited TiO2 (ML-TiO2) to control the photocurrent polarity according to irradiation wavelengths of visible and UV light. A pulsed laser deposition technique was employed to deposit the ML-TiO2 and NiO layers. The photoelectric properties were measured, and in situ spectroelectrochemical measurements were performed to investigate the relationship between the rectification properties of the plasmonic photoelectric conversion devices and the change in the Fermi level of the Au-NPs under UV light irradiation condition. Additionally, UV and visible light irradiation selectively induced the current of opposite polarity with the small applied voltage. The electron transfer phenomena from ML-TiO2 to Au-NPs and from Au-NPs to ML-TiO2 give us important information to understand plasmon-related charge separation.