Kadam Sujit A, Phan Giang Thi, Pham Duy Van, Patil Ranjit A, Lai Chien-Chih, Chen Yan-Ruei, Liou Yung, Ma Yuan-Ron
Department of Physics, National Dong Hwa University Hualien 97401 Taiwan
Center for Condensed Matter Sciences, National Taiwan University Taipei 10617 Taiwan.
Nanoscale Adv. 2021 Jul 29;3(19):5581-5588. doi: 10.1039/d1na00442e. eCollection 2021 Sep 28.
A tunable bandgap without doping is highly desirable for applications in optoelectronic devices. Herein, we develop a new method which can tune the bandgap without any doping. In the present research, the bandgap of FeO nanostructured films is simply tuned by changing the synthesis temperature. The FeO nanostructured films are synthesized on ITO/glass substrates at temperatures of 1100, 1150, 1200, and 1250 °C using the hot filament metal oxide vapor deposition (HFMOVD) and thermal oxidation techniques. The FeO nanostructured films contain two mixtures of Fe and Fe cations and two trigonal (α) and cubic (γ) phases. The increase of the Fe cations and cubic (γ) phase with the elevated synthesis temperatures lifted the valence band edge, indicating a reduction in the bandgap. The linear bandgap reduction of 0.55 eV without any doping makes the FeO nanostructured films promising materials for applications in bandgap engineering, optoelectronic devices, and energy storage devices.
对于光电器件应用而言，无需掺杂即可实现可调带隙是非常理想的。在此，我们开发了一种无需任何掺杂就能调节带隙的新方法。在本研究中，通过改变合成温度可简单地调节FeO纳米结构薄膜的带隙。使用热丝金属氧化物气相沉积（HFMOVD）和热氧化技术，在1100、1150、1200和1250℃的温度下在ITO/玻璃衬底上合成FeO纳米结构薄膜。FeO纳米结构薄膜包含Fe和Fe阳离子的两种混合物以及三角（α）相和立方（γ）相两种相。随着合成温度升高，Fe阳离子和立方（γ）相的增加提升了价带边缘，表明带隙减小。在无任何掺杂情况下线性带隙减小0.55eV，这使得FeO纳米结构薄膜成为带隙工程、光电器件和储能器件应用的有前景的材料。
