Electrical conductivity of germanium selenide nanosheets in oxygen and butane
文献类型：期刊论文
| 作者 | Dai Fang-Bo1; Yuan Jian-Mei3; Xu Kai-Yan3; Guo Zheng1; Zhao Hong-Quan2 ; Mao Yu-Liang1
|
| 刊名 | ACTA PHYSICA SINICA
 |
| 出版日期 | 2021-09-05 |
| 卷号 | 70期号:17页码:8 |
| ISSN号 | 1000-3290 |
| 关键词 | GeSe nanosheet electrical conductance gas adsorption first-principle |
| DOI | 10.7498/aps.70.20210325 |
| 通讯作者 | Zhao Hong-Quan(hqzhao@cigit.ac.cn) ; Mao Yu-Liang(ylmao@xtu.edu.cn) |
| 英文摘要 | As a type of two-dimensional (2D) semiconductor material, 2D germanium selenide (GeSe) exhibits excellent optoelectronic properties, and has potential applications in optoelectronic devices. The GeSe is a layered material with weak van der Waals interaction. Because of the high brittleness of GeSe, it is not easy to obtain 2D GeSe samples only by mechanical peeling technique. In order to obtain a thinner GeSe sheet, we use heat treatment to thin the bulk GeSe at a high temperature in vacuum. The GeSe samples obtained by mechanical peeling are placed in a tubular furnace with a pressure of 5 x 10(-4) Pa for high temperature heating and thinning. In order to explore the better thinning effect, we set four temperatures to be at 320, 330, 340 and 350 degrees C, respectively. After high temperature thinning, the samples are characterized and observed by atomic force microscope (AFM), scanning electron microscope (SEM), Raman spectrometer and photoluminescence (PL) spectrometer. From the above experiments, the GeSe nanosheet with a thickness of about 5 nm is prepared by mechanical peeling and high temperature thinning technology. Then, the electrical conductivities of GeSe nanosheets in oxygen (O-2) and butane (C4H10) with different concentrations are evaluated by our designed experimental device. The results show that with the increase of oxygen concentration, the electrical conductivity of GeSe nanosheets increases. When the GeSe nanosheet is in butane gas, its conductivity under the same voltage decreases with the increase of the concentration of butane gas. In order to further analyze the mechanism of gas adsorption on GeSe nanosheets, we carry out the first-principles calculations. Our calculation results show that the adsorption energy of GeSe nanosheets for oxygen and butane is -4.555 eV and -4.865 eV, respectively. It is shown that both adsorption systems have a certain stability. The adsorption energy of C4H10 is smaller than that of O-2, which corresponds to the smaller layer spacing of C4H10 than that of O-2 on GeSe surface. From Bader analysis, it is shown that 0.262e is transferred from the surface of GeSe nanosheet to O-2 molecule, which is much larger than 0.022e transferred from GeSe to C4H10 molecule. It can be inferred that the bond formed between GeSe and O-2 molecule is covalent bond, while GeSe adsorption C4H10 is very fragile hydrogen bond adsorption. In an ideal condition (single atomic GeSe layer, no Se vacancy, and the device preparation process is vacuum), our calculation results show that C4H10 still has a weak ability to obtain electrons from the GeSe nanosheet. However, the complex conditions such as the actual layer thickness, the appearance of Se vacancy and the adsorption of O-2 molecules on the surface leads to the difference between the experimental results and the theoretical calculations, which can be attributed to the adsorption of O-2 molecules on the GeSe surface from the air during the processing of GeSe thinning and device fabrication. Owing to the high density of Se vacancies in the thin film, the high density of O-2 adsorption is caused.Thus, butane gas is easy to lose electrons on the GeSe surface due to the O-2 adsorption. In other words, electrons are transferred from butane gas molecules to the surface of GeSe film and neutralized with holes, which reduces the concentration of carriers and the concentration of holes in GeSe film, thus reducing the conductivity. Our research will contribute to the application of GeSe nanosheets in optoelectronic devices at the atmosphere of oxygen and butane. |
| 资助项目 | Natural Science Foundation of Hunan Province, China[2019JJ40280] ; Research and Development Project of Key Field of Hunan Province, China[2019GK2101] ; Innovation Project of Degree and Postgraduate of Hunan Province, China[2020JGYB097] ; Innovation Project of Degree and Postgraduate of Hunan Province, China[2020JGYB098] ; Innovative Research Program for College Students of Hunan Province, China[S201910530020] |
| WOS研究方向 | Physics |
| 语种 | 英语 |
| 出版者 | CHINESE PHYSICAL SOC |
| WOS记录号 | WOS:000695077200032 |
| 源URL | [http://119.78.100.138/handle/2HOD01W0/14300]  |
| 专题 | 中国科学院重庆绿色智能技术研究院 |
| 通讯作者 | Zhao Hong-Quan; Mao Yu-Liang |
| 作者单位 | 1.Xiangtan Univ, Sch Phys & Optoelect, Xiangtan 411105, Peoples R China 2.Chinese Acad Sci, Chongqing Inst Green & Intelligent Technol, Chongqing 400714, Peoples R China 3.Xiangtan Univ, Sch Math & Computat Sci, Xiangtan 411105, Peoples R China |
| 推荐引用方式 GB/T 7714 | Dai Fang-Bo,Yuan Jian-Mei,Xu Kai-Yan,et al. Electrical conductivity of germanium selenide nanosheets in oxygen and butane[J]. ACTA PHYSICA SINICA,2021,70(17):8. |
| APA | Dai Fang-Bo,Yuan Jian-Mei,Xu Kai-Yan,Guo Zheng,Zhao Hong-Quan,&Mao Yu-Liang.(2021).Electrical conductivity of germanium selenide nanosheets in oxygen and butane.ACTA PHYSICA SINICA,70(17),8. |
| MLA | Dai Fang-Bo,et al."Electrical conductivity of germanium selenide nanosheets in oxygen and butane".ACTA PHYSICA SINICA 70.17(2021):8. |
入库方式： OAI收割
来源：重庆绿色智能技术研究院
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