Tunable electronic properties of two-dimensional C3N/antimonene van der Waals heterostructure

Abstract

Abstract In this work, we construct a C3N/antimonene van der Waals heterostructure to investigate its structural and electronic properties using first-principles calculations. The C3N/antimonene heterostructure exhibits an indirect band gap of 0.143 eV with a type-II band alignment. Electrons transferring from C3N to antimonene layer introduce a build-in electric field which can be used to prevent recombination of the photoexited electron–hole pairs. By applying vertical strain, band gap value of the heterostructure can be tuned in a range from 0 to 0.318 eV. A type-II to type-I band alignment transition occurs at a interlayer distance of sim3.2 Å, and the heterostructure experiences a semiconductor to metal transition with a interlayer distance of sim3.7 Å. Moreover, structural and electronic properties of C3N/antimonene heterostructure show modulation under in-plane biaxial strain. A semiconductor to metal transition takes place when strain reaches −2.0%. Moreover, with the increase of compressive strain, buckling degree of the heterostructure increases, and band gap of the heterostructure increases to 0.645 eV at strain of −5.0%. In addition, band gap value of the heterostructure varies almost linearly with vertical electric field of −0.2–0.2 V Å−1, and type-II band alignment can be maintained in this range. Thus, these results indicate that C3N/antimonene heterostructure has great potential in the field of multifunctional optoelectronic devices.