Band alignment control in a blue phosphorus/C2N van der Waals heterojunction using an electric field
Band alignment control in a blue phosphorus/C2N van der Waals heterojunction using an electric field
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使用电场控制蓝磷/C2N 范德华异质结中的能带对准
DOI：
10.1039/c9cp06696a
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发表时间：
2020
影响因子：
3.3
通讯作者：
Duan Li
中科院分区：
文献类型：
--
作者：
Zhang Zhihui;Xie Zifeng;Liu Jian;Tian Ye;Zhang Yan;Wei Xing;Guo Tingting;Ni Lei;Fan Jibin;Weng Yijun;Zha Zhengdi;Duan Li
利用密度泛函理论（DFT）计算研究了蓝磷/C2N范德华（vdW）异质结的可控能带工程。异质结具有天然的ii型带对准，直接带隙值为1.514 eV，这为太阳能电池的应用提供了巨大的潜力。当异质结在太阳照射下时，光产生的电子-空穴对可以在不同的单层上有效分离。它诱导空间间接激子的形成。此外，还发现该异质结的带隙相对于垂直外电场呈近似线性变化。非常有趣的是，当外加电场为- 0.2 V Å−1时，从ii型到i型的带对准变化发生了。这一特性为获得新型多功能器件提供了诱人的可能性。
Well-controlled band engineering of a blue phosphorus/C2N van der Waals (vdW) heterojunction is investigated by density functional theory (DFT) calculations. The heterojunction has a natural type-II band alignment with a direct band gap value of 1.514 eV, which gives the enormous potential for solar cell applications. When the heterojunction is under solar illumination, the photogenerated electron–hole pairs can separate out on the disparate monolayers effectively. It induces the formation of spatially indirect excitons. Furthermore, it is found that the band gap of this heterojunction exhibits approximately linear variation with respect to the perpendicular external electric field. Very interestingly, a band alignment change from type-II to type-I occurs at an applied electric field of −0.2 V Å−1. This characteristic provides an attractive possibility to obtain novel multifunctional devices.