Phosphorene, an elemental 2D material, which is the monolayer of black phosphorus, has been mechanically exfoliated recently. In its bulk form, black phosphorus shows high carrier mobility (~10000 cm2/Vs) and a ~0.3 eV direct bandgap. Well-behaved p-type field-effect transistors with mobilities of up to 1000 cm2/Vs, as well as phototransistors, have been demonstrated on few-layer black phosphorus, showing its promise for electronics and optoelectronics applications due to its high hole mobility and thickness-dependence direct bandgap. However, p-n junctions, the basic building blocks of modern electronic and optoelectronic devices, have not yet been realized based on black phosphorus. In this paper, we demonstrate a gate tunable p-n diode based on a p-type black phosphorus/n-type monolayer MoS2 van der Waals p-n heterojunction. Upon illumination, these ultra-thin p-n diodes show a maximum photodetection responsivity of 418 mA/W at the wavelength of 633 nm, and photovoltaic energy conversion with an external quantum efficiency of 0.3%. These p-n diodes show promise for broadband photodetection and solar energy harvesting.
@article{arxiv.1407.3430,
title = {Black Phosphorus-Monolayer MoS2 van der Waals Heterojunction P-N Diode},
author = {Yexin Deng and Zhe Luo and Nathan J. Conrad and Han Liu and Yongji Gong and Sina Najmaei and Pulickel M. Ajayan and Jun Lou and Xianfan Xu and Peide D. Ye},
journal= {arXiv preprint arXiv:1407.3430},
year = {2014}
}