Nanocomposites and nanomaterials
Strategy of creating integrated lateral p-n junctions in two-dimensional materials by adsorption of atoms or molecules
Balabai R., Solomenko A.
Kryvyi Rih St. Pedagogical Un., 54 Gagarina Ave., Kryvyi Rih, 50086, Ukraine.
E-mail: solomenko.anastasiia@gmail.com

The reduced thickness of 2D materials gives them a high sensitivity to the environment surrounding their surface. Molecules physisorbed or chemisorbed onto the surface can influence transport in the 2D material for example by introducing doping effects and a p-n junction can thus be fabricated by locally doping the material. This principle has been used to fabricate chemically doped p-n junctions with graphene, transition metal dichalcogenides and black phosphorous [1]. For example, a chemically doped MoS2 p-n junction was reported by Choi and coauthors [2]. Chemical doping with benzyl viologen molecules modulates the electron density and allows acquiring a large built-in potential in in-plane black phosphorene p-n junction [3].
In this case, based on the previous research [4], our study was to compare the effects of physical and chemical adsorption on the appearance of integrated lateral p-n junctions in two-dimensional materials. For this purpose the valence electron density spatial distribution, the densities of electron states, the band gaps and the core charges have been calculated in the framework of the electronic density functional and ab initio pseudopotential based on own program code [5].

1.	Frisenda R., Molina-Mendoza A. J., Mueller T., Castellanos-Gomez A.,  Herre van der Zant S. J. Atomically thin p–n junctions based on two-dimensional materials // Chem. Soc. Rev.-2018.-47.- P. 3339-3358.
2.	Choi M. S., Qu D., Lee D., Liu X., Watanabe K., Taniguchi T., Yoo W. J. Lateral MoS2 p-n junction formed by chemical doping for use in high-performance optoelectronics // ACS Nano.-2014.-8.-P. 9332-9340.
3.	Yu X, Zhang Sh., Zeng H., Wang Q. J. Lateral black phosphorene p-n junctions formed via chemical doping for high performance near-infrared photodetector. Nano Energy.-2016.-25.-P. 34-41.
4.	Balabai R.M., Lubenetsz A.G. Lateral Junctions Based on Graphene with different doping regions // Journal of Nano- and Electronic Physics.-2017.-9, N 05017.-P. 1-8. 
5.	Ab initio calculation [E-resource]. – Access mode: http://sites.google.com/a/kdpu.edu.ua/calculationphysics