▎ 摘　　要

In this work, we propose an ultrathin graphene/Ca(OH)(2) van der Waals heterostructure (vdWH) and investigate its structural stability, electronic structures and Schottky contact types modulation by ab initio calculations. Our results show the preservation of graphene and Ca(OH)(2) intrinsic electronic properties in graphene/Ca(OH)(2) vdWH, which is mainly characterized by the physicoadsorption interaction with the binding energy of -33.37 meV per carbon atom. Ca(OH)(2) monolayer stacking on graphene to form the vdWH forms the p-type Schottky contact and opens a valuable graphene's band gap of 9.7 meV, suggesting its promising application in high speed nanoelectronic devices. Furthermore, electric field and vertical strain can be used to modulate the Schottky contact from the p-type to the n-type one and to Ohmic contact. These predictions demonstrate the potential candidate of the G/Ca(OH)(2) vdWH for future nanoelectronic applications.