The electronic and interfacial properties of a vdW heterostructure composed of penta-PdSe2 and biphenylene monolayers

Abstract

It is of current interest to develop van der Waals (vdW) heterostructures with tunable electronic properties for technical applications. Motivated by the synthesis of a metallic carbon nanosheet termed the biphenylene network (BPN) [Q. Fan, L. Yan, M. W. Tripp, O. Krejčí, S. Dimosthenous, S. R. Kachel, M. Chen, A. S. Foster, U. Koert, P. Liljeroth et al., Science, 2021, 372, 852–856] and semiconducting penta-PdSe₂ sheets [A. D. Oyedele, S. Yang, L. Liang, A. A. Puretzky, K. Wang, J. Zhang, P. Yu, P. R. Pudasaini, A. W. Ghosh, Z. Liu et al., J. Am. Chem. Soc., 2017, 139, 14090–14097], we rationally design a vdW heterostructure by vertically stacking these two individual sheets. The state-of-the-art first-principles calculations show that the penta-PdSe₂ sheet well preserves its intrinsic properties when forming a vdW contact with BPN. The heterostructure possesses an n-type Schottky contact with a Schottky barrier of 0.54 eV, and a negative band-bending of 0.56 eV at the lateral interface with electrons as major transport carriers. These features make the penta-PdSe₂/BPN heterojunction promising for applications in field-effect transistors.