从2D vdW异构结构中的I型到III型的组合调制介导带对齐工程
Dingli Guo1,2, Qiang Fu1, Guitao Zhang1
1School of Physics and Key Laboratory of Quantum Materials and Devices of Ministry of Education, Southeast University, Nanjing, 211189, China.
Advanced materials (Deerfield Beach, Fla.)
|August 10, 2024
概括
在WSe2/Bi2Te3-xSex范德瓦尔斯异构结构 (vdWHs) 中的带对齐工程从I型调整为III型. 这种调整会影响光电探测器的性能,并提高发光二极管 (LED) 的效率.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术 纳米技术
背景情况:
- 带对齐工程对于优化光电子设备 (如光探测器和发光二极管 (LED)) 中的电荷动态至关重要.
- 范德瓦尔斯异构结构 (vdWHs) 中带偏移对设备性能指标的影响仍未得到充分研究.
- WSe2/Bi2Te3-xSex vdWHs提供了一个可调的平台,用于调查频段对齐效应.
研究的目的:
- 系统地调查可调频带对齐对WSe2/Bi2Te3-xSex vdWHs的性能的影响.
- 为了将频段对齐 (I型到III型) 的变化与光电子设备特征相关联.
- 为了证明工程带对齐对先进的光探测器和LED的潜力.
主要方法:
- 化学蒸汽沉积 (CVD) 用于合成不同组成 (0 ≤ x ≤ 3) 的WSe2/Bi2Te3-xSex vdWHs.
- 使用实验性表征和理论计算的组合来确定带对齐.
- 基于VDWH的光探测器和LED的制造和测试是为了评估设备性能而进行的.
主要成果:
- WSe2/Bi2Te3-xSex vdWHs 的带调整成功地从I型 (WSe2/Bi2Te3) 调整为III型 (WSe2/Bi2Se3).
- 基于I型vdWHs的光探测器表现出高响应度 (58.12A/W) 和检测能力 (2.91×10^12Jones),而III型vdWHs显示出超快的光响应 (3.2μs).
- 基于vdWH的III型LED在室温下表现出优越的发光率和电解发光外部量子效率 (EQE),与其他过渡金属二甲基化物 (TMD) p-n二极管相比.
结论:
- 在WSe2/Bi2Te3-xSex vdWH中调节带对齐显著影响光电子设备的性能.
- 从I型到III型频段对齐的过渡为光电探测器和LED提供了明显的优势.
- 工程带对齐是设计基于VDWHs的高性能光电子设备的一个有前途的策略.
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